| 1. |
- Aamodt, K., et al.
(author)
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The ALICE experiment at the CERN LHC
- 2008
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In: Journal of Instrumentation. - 1748-0221. ; 3:S08002
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Research review (peer-reviewed)abstract
- ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries, Its overall dimensions are 16 x 16 x 26 m(3) with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008.
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| 2. |
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| 3. |
- Abate, E., et al.
(author)
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Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors
- 2008
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In: Journal of Instrumentation. - 1748-0221. ; 3
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Journal article (peer-reviewed)abstract
- The ATLAS (A Toroidal LHC ApparatuS) Inner Detector provides charged particle tracking in the centre of the ATLAS experiment at the Large Hadron Collider (LHC). The Inner Detector consists of three subdetectors: the Pixel Detector, the Semiconductor Tracker (SCT), and the Transition Radiation Tracker (TRT). This paper summarizes the tests that were carried out at the final stage of SCT+TRT integration prior to their installation in ATLAS. The combined operation and performance of the SCT and TRT barrel and endcap detectors was investigated through a series of noise tests, and by recording the tracks of cosmic rays. This was a crucial test of hardware and software of the combined tracker detector systems. The results of noise and cross-talk tests on the SCT and TRT in their final assembled configuration, using final readout and supply hardware and software, are reported. The reconstruction and analysis of the recorded cosmic tracks allowed testing of the offline analysis chain and verification of basic tracker performance parameters, such as efficiency and spatial resolution, in combined operation before installation.
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| 4. |
- Abdesselam, A., et al.
(author)
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Engineering for the ATLAS SemiConductor Tracker (SCT) end-cap
- 2008
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In: Journal of Instrumentation. - 1748-0221. ; 3
-
Journal article (peer-reviewed)abstract
- The ATLAS SemiConductor Tracker (SCT) is a silicon-strip tracking detector which forms part of the ATLAS inner detector. The SCT is designed to track charged particles produced in proton-proton collisions at the Large Hadron Collider (LHC) at CERN at an energy of 14 TeV. The tracker is made up of a central barrel and two identical end-caps. The barrel contains 2112 silicon modules, while each end-cap contains 988 modules. The overall tracking performance depends not only on the intrinsic measurement precision of the modules but also on the characteristics of the whole assembly, in particular, the stability and the total material budget. This paper describes the engineering design and construction of the SCT end-caps, which are required to support mechanically the silicon modules, supply services to them and provide a suitable environment within the inner detector. Critical engineering choices are highlighted and innovative solutions are presented - these will be of interest to other builders of large-scale tracking detectors. The SCT end-caps will be fully connected at the start of 2008. Further commissioning will continue, to be ready for proton-proton collision data in 2008.
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| 5. |
- Abdesselam, A., et al.
(author)
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The ATLAS semiconductor tracker end-cap module
- 2007
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 575:3, s. 353-389
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Journal article (peer-reviewed)abstract
- The challenges for the tracking detector systems at the LHC are unprecedented in terms of the number of channels, the required read-out speed and the expected radiation levels. The ATLAS Semiconductor Tracker. (SCT) end-caps have a total of about 3 million electronics channels each reading out every 25 ns into its own on-chip 3.3 mu s buffer. The highest anticipated dose after 10 years operation is 1.4x10(14) cm(-2) in units of 1 MeV neutron equivalent (assuming the damage factors scale with the non-ionising energy loss). The forward tracker has 1976 double-sided modules, mostly of area similar to 70 cm(2), each having 2 x 768 strips read out by six ASICs per side. The requirement to achieve an average perpendicular radiation length of 1.5% X-0, while coping with up to 7 W dissipation per module (after irradiation), leads to stringent constraints on the thermal design. The additional requirement of 1500e(-) equivalent noise charge (ENC) rising to only 1800e(-) ENC after irradiation, provides stringent design constraints on both the high-density Cu/Polyimide flex read-out circuit and the ABCD3TA read-out ASICs. Finally, the accuracy of module assembly must not compromise the 16 mu m (r phi) resolution perpendicular to the strip directions or 580 mu m radial resolution coming from the 40 mrad front-back stereo angle. A total of 2210 modules were built to the tight tolerances and specifications required for the SCT. This was 234 more than the 1976 required and represents a yield of 93%. The component flow was at times tight, but the module production rate of 40-50 per week was maintained despite this. The distributed production was not found to be a major logistical problem and it allowed additional flexibility to take advantage of where the effort was available, including any spare capacity, for building the end-cap modules. The collaboration that produced the ATLAS SCT end-cap modules kept in close contact at all times so that the effects of shortages or stoppages at different sites could be rapidly resolved.
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| 6. |
- Abdesselam, A., et al.
(author)
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The barrel modules of the ATLAS semiconductor tracker
- 2006
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In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 568:2, s. 642-671
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Journal article (peer-reviewed)abstract
- This paper describes the silicon microstrip modules in the barrel section of the SemiConductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The module requirements, components and assembly techniques are given, as well as first results of the module performance on the fully assembled barrels that make up the detector being installed in the ATLAS experiment.
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| 7. |
- Coustenis, A., et al.
(author)
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TandEM : Titan and Enceladus mission
- 2009
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In: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 23:3, s. 893-946
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Journal article (peer-reviewed)abstract
- TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (MontgolfiSre) and possibly several landing probes to be delivered through the atmosphere.
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| 8. |
- Aksyutina, Yu, et al.
(author)
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Lithium isotopes beyond the drip line
- 2008
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In: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 666:5, s. 430-434
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Journal article (peer-reviewed)abstract
- The unbound isotopes 10Li, 12Li and 13Li have been observed after nucleon-knockout reactions at relativistic energies with 11Li and 14Be beams impinging on a liquid hydrogen target. The channels , and were analysed in the ALADIN-LAND setup at GSI. The 10Li data confirm earlier findings, while the 12Li and 13Li nuclei were observed for the first time. The relative-energy spectrum shows that the ground state of 12Li can be described as a virtual s-state with a scattering length of -13.7(1.6) fm. A broad energy spectrum was found for the channel. Based on the assumption that the relative-energy spectrum is dominated by a correlated background presumably stemming from initial correlations in the 14Be ground-state, evidence for a 13Li resonance at 1.47(31) MeV above the threshold with a width around 2 MeV has been found.
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| 9. |
- Aksyutina, Yuliya, 1983, et al.
(author)
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Properties of the 7He ground state from 8He neutron knockout
- 2009
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In: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 679:3, s. 191-196
-
Journal article (peer-reviewed)abstract
- The unbound nucleus 7He, produced in neutron-knockout reactions with a 240 MeV/u 8He beam in a liquid-hydrogen target, has been studied in an experiment at the ALADIN-LAND setup at GSI. From an R-matrix analysis the resonance parameters for 7He as well as the spectroscopic factor for the 6He(0+) + n configuration in its ground-state have been obtained. The spectroscopic factor is 0.61 confirming that 7He is not a pure single-particle state. An analysis of 5He data from neutron-knockout reactions of 6He in a carbon target reveals the presence of an s-wave component at low energies in the α+n relative energy spectrum. A possible low-lying exited state in 7He observed in neutron knockout data from 8He in a carbon target and tentatively interpreted as a Iπ=1/2− state, could not be observed in the present experiment. Possible explanations of the shape difference between the 7He resonance obtained in the two knockout reactions are discussed in terms of target-dependence or different reaction mechanisms at relativistic energies.
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| 10. |
- Jeppesen, H. B., et al.
(author)
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Investigation of the Li-9+H-2 -> Li-8+t reaction at REX-ISOLDE
- 2006
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In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 635, s. 17-17
-
Journal article (peer-reviewed)abstract
- The one-neutron transfer reaction Li-9 + H-2 -> Li-8 + t has been investigated in an inverse kinematics experiment by bombarding a deuterated polypropylene target with a 2.36 MeV/u Li-9 beam from the post-accelerator REX-ISOLDE at CERN. Excitation energies in Li-8 as well as angular distributions of the tritons were obtained and spectroscopic factors deduced. (c) 2006 Elsevier B.V. All rights reserved.
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| 11. |
- Jeppesen, H. B., et al.
(author)
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Low energy reactions with radioactive ions at REX-ISOLDE - the Li-9+H-2 case
- 2005
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In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 748, s. 374-374
-
Journal article (peer-reviewed)abstract
- At the newly constructed postaccelerator REX-ISOLDE (Radioactive beam Experiment at ISOLDE) we have investigated reactions induced by a Li-9 beam incident on a deuterium target at an energy of 2.36 MeV/u. Most reaction channels were recorded. From one-neutron transfer the differential cross-section for the low lying Li-10 spectrum is found. The results from the other channels demonstrate the great applicability and many possibilities that REX-ISOLDE opens up.
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| 12. |
- Kerzenmacher, T., et al.
(author)
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Validation of NO2 and NO from the Atmospheric Chemistry Experiment (ACE)
- 2008
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In: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 8:19, s. 5801--5841-
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Journal article (peer-reviewed)abstract
- Vertical profiles of NO2 and NO have been obtained from solar occultation measurements by the Atmospheric Chemistry Experiment (ACE), using an infrared Fourier Transform Spectrometer (ACE-FTS) and (for NO2) an ultraviolet-visible-near-infrared spectrometer, MAESTRO (Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation). In this paper, the quality of the ACE-FTS version 2.2 NO2 and NO and the MAESTRO version 1.2 NO2 data are assessed using other solar occultation measurements (HALOE, SAGE II, SAGE III, POAM III, SCIAMACHY), stellar occultation measurements (GOMOS), limb measurements (MIPAS, OSIRIS), nadir measurements (SCIAMACHY), balloon-borne measurements (SPIRALE, SAOZ) and ground-based measurements (UV-VIS, FTIR). Time differences between the comparison measurements were reduced using either a tight coincidence criterion, or where possible, chemical box models. ACE-FTS NO2 and NO and the MAESTRO NO2 are generally consistent with the correlative data. The ACE-FTS and MAESTRO NO2 volume mixing ratio (VMR) profiles agree with the profiles from other satellite data sets to within about 20% between 25 and 40 km, with the exception of MIPAS ESA (for ACE-FTS) and SAGE II (for ACE-FTS (sunrise) and MAESTRO) and suggest a negative bias between 23 and 40 km of about 10%. MAESTRO reports larger VMR values than the ACE-FTS. In comparisons with HALOE, ACE-FTS NO VMRs typically (on average) agree to ±8% from 22 to 64 km and to +10% from 93 to 105 km, with maxima of 21% and 36%, respectively. Partial column comparisons for NO2 show that there is quite good agreement between the ACE instruments and the FTIRs, with a mean difference of +7.3% for ACE-FTS and +12.8% for MAESTRO.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
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| 17. |
- Carr, C., et al.
(author)
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RPC : The rosetta plasma consortium
- 2007
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In: Space Science Reviews. - : Springer Science and Business Media LLC. - 0038-6308 .- 1572-9672. ; 128:1-4, s. 629-647
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Research review (peer-reviewed)abstract
- The Rosetta Plasma Consortium (RPC) will make in-situ measurements of the plasma enviromnent of comet 67P/Churyumov-Gerasimenko. The consortium will provide the complementary data sets necessary for an understanding of the plasma processes in the inner coma, and the structure and evolution of the coma with the increasing cometary activity. Five sensors have been selected to achieve this: the Ion and Electron Sensor (IES), the Ion Composition Analyser (ICA), the Langmuir Probe (LAP), the Mutual Impedance Probe (MIP) and the Magnetometer (MAG). The sensors interface to the spacecraft through the Plasma Interface Unit (PIU). The consortium approach allows for scientific, technical and operational coordination, and makes Optimum use of the available mass and power resources.
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| 18. |
- Chulkov, L. V., et al.
(author)
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Three-body correlations in electromagnetic dissociation of Borromean nuclei: The He-6 case
- 2005
-
In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 759:1-2, s. 23-42
-
Journal article (peer-reviewed)abstract
- Dissociation of He-6 on a lead target has been studied at 240 MeV/u. The four-momenta of the two neutrons in coincidence with alpha-particles have been measured and used to reconstruct the three-body energy and angular correlations in the final state. For the first time, three-body correlations were included in the analysis of the He-6 dissociation data, and compared with calculations assuming a dipole mode for the electromagnetic dissociation. In addition, the experimental data have been analyzed using a series expansion of the final transition amplitude into hyperspherical functions, showing the importance of both nn and alpha n final-state interactions. It is shown that the dissociation process is governed by a transition of one neutron from the p-shell in the 6He ground state to the s-shell in the continuum further indicating that the role of the transition through an intermediate He-5(3/2(-)) state is more important than expected. (c) 2005 Elsevier B.V. All rights reserved.
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| 19. |
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| 20. |
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| 21. |
- Hertegard, S., et al.
(author)
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Viscoelastic and histologic properties in scarred rabbit vocal folds after mesenchymal stem cell injection
- 2006
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In: The Laryngoscope. - : Wiley-Blackwell. - 0023-852X .- 1531-4995. ; 116:7, s. 1248-1254
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Journal article (peer-reviewed)abstract
- OBJECTIVE/HYPOTHESIS:The aim of this study was to analyze the short-term viscoelastic and histologic properties of scarred rabbit vocal folds after injection of human mesenchymal stem cells (MSC) as well as the degree of MSC survival. Because MSCs are antiinflammatory and regenerate mesenchymal tissues, can MSC injection reduce vocal fold scarring after injury?STUDY DESIGN:Twelve vocal folds from 10 New Zealand rabbits were scarred by a localized resection and injected with human MSC or saline. Eight vocal folds were left as controls.MATERIAL AND METHODS:After 4 weeks, 10 larynges were stained for histology and evaluation of the lamina propria thickness. Collagen type I content was analyzed from six rabbits. MSC survival was analyzed by fluorescent in situ hybridization staining from three rabbits. Viscoelasticity for 10 vocal folds was analyzed in a parallel-plate rheometer.RESULTS:The rheometry on fresh-frozen samples showed decreased dynamic viscosity and lower elastic modulus (P<.01) in the scarred samples injected with MSC as compared with the untreated scarred group. Normal controls had lower dynamic viscosity and elastic modulus as compared with the scarred untreated and treated vocal folds (P<.01). Histologic analysis showed a higher content of collagen type 1 in the scarred samples as compared with the normal vocal folds and with the scarred folds treated with MSC. MSCs remained in all samples analyzed.CONCLUSIONS:The treated scarred vocal folds showed persistent MSC. Injection of scarred rabbit vocal folds with MSC rendered improved viscoelastic parameters and less signs of scarring expressed as collagen content in comparison to the untreated scarred vocal folds.
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| 22. |
- Niedermaier, O., et al.
(author)
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"Safe" Coulomb excitation of Mg-30
- 2005
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In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 94:17, s. 172501 (artno)-
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Journal article (peer-reviewed)abstract
- We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient γ spectrometer MINIBALL. Using Mg-30 ions accelerated to an energy of 2.25 MeV/u together with a thin Ni-nat target, Coulomb excitation of the first excited 2(+) states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation γ-ray yields the B(E2;0(gs)(+)&RARR; 2(1)(+)) value of Mg-30 was determined to be 241(31)e(2) fm(4). Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope Mg-30 resides outside the "island of inversion."
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| 23. |
- Niedermaier, O., et al.
(author)
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The neutron-rich Mg isotopes: first results from MINIBALL at REX-ISOLDE
- 2005
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In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 752, s. 273-273
-
Journal article (peer-reviewed)abstract
- We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient γ spectrometer MINIBALL. Using Mg-30 ions accelerated to an energy of 2.25 MeV/u together with a thin Ni-nat target, Coulomb excitation of the first excited 2(+) states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation γ-ray yields the B(E2;0(gs)(+)&RARR; 2(1)(+)) value of Mg-30 was determined to be 241(31)e(2) fm(4). Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope Mg-30 resides outside the "island of inversion."
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| 24. |
- Scheit, H., et al.
(author)
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Coulomb excitation of neutron-rich beams at REX-ISOLDE
- 2005
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In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-601X .- 1434-6001. ; 25:Suppl. 1, s. 397-402
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Conference paper (peer-reviewed)abstract
- After the successful commissioning of the radioactive beam experiment at ISOLDE (REX-ISOLDE) - an accelerator for exotic nuclei produced by ISOLDE - in 2002 and the promotion to a CERN user facility in 2003, first physics experiments using these beams were performed. Initial experiments focused on the region of deformation in the vicinity of the neutron-rich Na and Mg isotopes. Preliminary results on the neutron-rich Na and Mg isotopes show the high potential and physics opportunities offered by the exotic isotope accelerator REX in conjunction with the modern Germanium gamma spectrometer MINIBALL.
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| 25. |
- Smith, A., et al.
(author)
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LunarEX-a proposal to cosmic vision
- 2009
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In: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 23:3, s. 711-740
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Journal article (peer-reviewed)
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| 26. |
- Adewumi, Oluseun, et al.
(author)
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Characterization of human embryonic stem cell lines by the International Stem Cell Initiative
- 2007
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In: Nature Biotechnology. - : Springer Science and Business Media LLC. - 1087-0156 .- 1546-1696. ; 25:7, s. 803-816
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Journal article (peer-reviewed)abstract
- The International Stem Cell Initiative characterized 59 human embryonic stem cell lines from 17 laboratories worldwide. Despite diverse genotypes and different techniques used for derivation and maintenance, all lines exhibited similar expression patterns for several markers of human embryonic stem cells. They expressed the glycolipid antigens SSEA3 and SSEA4, the keratan sulfate antigens TRA-1-60, TRA-1-81, GCTM2 and GCT343, and the protein antigens CD9, Thy1 (also known as CD90), tissue- nonspecific alkaline phosphatase and class 1 HLA, as well as the strongly developmentally regulated genes NANOG, POU5F1 (formerly known as OCT4), TDGF1, DNMT3B, GABRB3 and GDF3. Nevertheless, the lines were not identical: differences in expression of several lineage markers were evident, and several imprinted genes showed generally similar allele-specific expression patterns, but some gene-dependent variation was observed. Also, some female lines expressed readily detectable levels of XIST whereas others did not. No significant contamination of the lines with mycoplasma, bacteria or cytopathic viruses was detected.
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| 27. |
- Alagia, M, et al.
(author)
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Angular effects in autoionization of 3 P doubly excited states in He
- 2009
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In: Journal of Physics: Conference Series. ; 194
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Journal article (peer-reviewed)abstract
- The first members of dipole allowed 3 P o doubly excited series in helium have been observed in resonant photoexcitation of 1 s 2 s 3 S e metastable atoms. A good agreement measured relative photoionization cross sections is achieved when theory includes the radiation damping and, also important, the effects of spin-orbit multiplet splitting on electron angular distribution.
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| 28. |
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| 29. |
- Alagia, M., et al.
(author)
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Excitation of 1S and 3S Metastable Helium Atoms to Doubly Excited States
- 2009
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:15, s. 153001-
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Journal article (peer-reviewed)abstract
- We present spectra of triplet and singlet metastable helium atoms resonantly photoexcited to doubly excited states. The first members of three dipole-allowed 1,3Po series have been observed and their relative photoionization cross sections determined, both in the triplet (from 1s2s 3Se) and singlet (from 1s2s 1Se) manifolds. The intensity ratios are drastically different with respect to transitions from the ground state. When radiation damping is included the results for the singlets are in agreement with theory, while for triplets spin-orbit interaction must also be taken into account.
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| 30. |
- Askmyr, Maria K, et al.
(author)
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Towards a better understanding and new therapeutics of osteopetrosis.
- 2008
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In: British journal of haematology. - : Wiley. - 1365-2141 .- 0007-1048. ; 140:6, s. 597-609
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Research review (peer-reviewed)abstract
- Lack of or dysfunction in osteoclasts result in osteopetrosis, a group of rare but often severe, genetic disorders affecting skeletal tissue. Increase in bone mass results in skeletal malformation and bone marrow failure that may be fatal. Many of the underlying defects have lately been characterized in humans and in animal models of the disease. In humans, these defects often involve mutations in genes expressing proteins involved in the acidification of the osteoclast resorption compartment, a process necessary for proper bone degradation. So far, the only cure for children with severe osteopetrosis is allogeneic hematopoietic stem cell (HSC) transplantation but without a matching donor this form of therapy is far from optimal. The characterization of the genetic defects opens up the possibility for gene replacement therapy as an alternative. Accordingly, HSC-targeted gene therapy in a mouse model of infantile malignant osteopetrosis was recently shown to correct many aspects of the disease.
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| 31. |
- Askmyr, Maria, et al.
(author)
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Low-dose busulphan conditioning and neonatal stem cell transplantation preserves vision and restores hematopoiesis in severe murine osteopetrosis.
- 2009
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In: Experimental Hematology. - : Elsevier BV. - 1873-2399 .- 0301-472X. ; 37, s. 302-308
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Infantile malignant osteopetrosis is a fatal disease caused by lack of functional osteoclasts. In most of patients, TCIRG1, encoding a subunit of a proton pump essential for bone resorption, is mutated. Osteopetrosis leads to bone marrow failure and blindness due to optic nerve compression. Oc/oc mice have a deletion in Tcirg1 and die around 3 to 4 weeks, but can be rescued by neonatal stem cell transplantation (SCT) after irradiation conditioning. However, as irradiation of neonatal mice results in retinal degeneration, we wanted to investigate whether conditioning with busulphan prior to SCT can lead to preservation of vision and reversal of osteopetrosis in the oc/oc mouse model. MATERIALS AND METHODS: Pregnant dams were conditioned with busulphan and their litters transplanted with 1 x 10(6) normal lineage-depleted bone marrow cells intravenously or intraperitoneally. Mice were followed in terms of survival and engraftment level, as well as with peripheral blood lineage analysis, bone and eye histopathology and a visual-tracking drum test to assess vision. RESULTS: Busulphan at 15 mg/kg was toxic to oc/oc mice. However, six of seven oc/oc mice conditioned with busulphan 7.5 mg/kg survived past the normal lifespan with 10% engraftment, correction of the skeletal phenotype, and normalization of peripheral blood lineages. Busulphan, in contrast to irradiation, did not have adverse effects on the retina as determined by histopathology, and 8 weeks after transplantation control and oc/oc mice retained their vision. CONCLUSION: Low-dose busulphan conditioning and neonatal SCT leads to prolonged survival of oc/oc mice, reverses osteopetrosis and prevents blindness even at low engraftment levels.
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| 32. |
- Battin, Tom J., et al.
(author)
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The boundless carbon cycle
- 2009
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In: Nature Geoscience. - : Springer Science and Business Media LLC. - 1752-0894 .- 1752-0908. ; 2:9, s. 598-600
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Journal article (peer-reviewed)
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| 33. |
- Brose, Ulrich, et al.
(author)
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Body sizes of consumers and their resources
- 2005
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In: Ecology. - : Ecological Society of America. - 0012-9658 .- 1939-9170. ; 86:9, s. 2545-2545
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Journal article (peer-reviewed)abstract
- Trophic information—who eats whom—and species’ body sizes are two of the most basic descriptions necessary to understand community structure as well as ecological and evolutionary dynamics. Consumer–resource body size ratios between predators and their prey, and parasitoids and their hosts, have recently gained increasing attention due to their important implications for species’ interaction strengths and dynamical population stability. This data set documents body sizes of consumers and their resources. We gathered body size data for the food webs of Skipwith Pond, a parasitoid community of grass-feeding chalcid wasps in British grasslands; the pelagic community of the Benguela system, a source web based on broom in the United Kingdom; Broadstone Stream, UK; the Grand Caric¸aie marsh at Lake Neuchaˆtel, Switzerland; Tuesday Lake, USA; alpine lakes in the Sierra Nevada of California; Mill Stream, UK; and the eastern Weddell Sea Shelf, Antarctica. Further consumer–resource body size data are included for planktonic predators, predatory nematodes, parasitoids, marine fish predators, freshwater invertebrates, Australian terrestrial consumers, and aphid parasitoids. Containing 16 807 records, this is the largest data set ever compiled for body sizes of consumers and their resources. In addition to body sizes, the data set includes information on consumer and resource taxonomy, the geographic location of the study, the habitat studied, the type of the feeding interaction (e.g., predacious, parasitic) and the metabolic categories of the species (e.g., invertebrate, ectotherm vertebrate). The present data set was gathered with the intent to stimulate research on effects of consumer–resource body size patterns on food-web structure, interaction-strength distributions, population dynamics, and community stability. The use of a common data set may facilitate cross-study comparisons and understanding of the relationships between different scientific approaches and models.
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| 34. |
- Coreno, M, et al.
(author)
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A new system for photon induced fluorescence spectroscopy applied to the study of doubly excited states of helium
- 2005
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In: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048. ; 144-147, s. 39-42
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Journal article (peer-reviewed)abstract
- A new system for photon induced fluorescence spectroscopy (PIFS) at the gas phase photoemission beamline (Elettra, Trieste) is described. It consists of a novel non-dispersive detector for VUV photons and a spectrometer for UV/visible light with cooled CCD detector. To illustrate the performance of the apparatus, the fluorescence decay of the doubly excited states of helium below the N = 2 ionization threshold has been studied. Fluorescence emission from both singlet and triplet states has been observed, and in particular weak visible emission resulting from decay of 7(3D) and 8(3D) triplet states confirmed the recently published assignment of these states. This illustrates how PIFS can be used to provide a direct and unambiguous verification of the assignments of states observed in photoabsorption.
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| 35. |
- Edberg, Niklas J. T., et al.
(author)
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Simultaneous measurements of Martian plasma boundaries by Rosetta and Mars Express
- 2009
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In: Planetary and Space Science. - : Elsevier BV. - 0032-0633 .- 1873-5088. ; 57:8-9, s. 1085-1096
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Journal article (peer-reviewed)abstract
- We present the first two-spacecraft near-simultaneous observations of the Martian bow shock (BS), magnetic pileup boundary (MPB) and photo-electron boundary (PEB) obtained by the plasma instruments onboard Rosetta and Mars Express during the Rosetta Mars fly by on February 25, 2007. Our observations are compared with shape models for the BS and MPB derived from previous statistical studies. The MPB is found at its expected position but the BS for this event is found significantly closer to the planet than expected for the rather slow and moderately dense solar wind. Cross-calibration of the density measurements on the two spacecraft gives a density profile through the magnetosheath, indicating an increasing solar wind flux during the Rosetta passage which is consistent with the multiple BS crossings at the Rosetta exit.
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| 36. |
- Edberg, Niklas, et al.
(author)
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Rosetta and Mars Express observations of the influence of high solar wind pressure on the Martian plasma environment
- 2009
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In: Annales Geophysicae. - : Copernicus GmbH. - 0992-7689 .- 1432-0576. ; 27:12, s. 4533-4545
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Journal article (peer-reviewed)abstract
- We report on new simultaneous in-situ observations at Mars from Rosetta and Mars Express (MEX) on how the Martian plasma environment is affected by high pressure solar wind. A significant sharp increase in solar wind density, magnetic field strength and turbulence followed by a gradual increase in solar wind velocity is observed during similar to 24 h in the combined data set from both spacecraft after Rosetta's closest approach to Mars on 25 February 2007. The bow shock and magnetic pileup boundary are coincidently observed by MEX to become asymmetric in their shapes. The fortunate orbit of MEX at this time allows a study of the inbound boundary crossings on one side of the planet and the outbound crossings on almost the opposite side, both very close to the terminator plane. The solar wind and interplanetary magnetic field (IMF) downstream of Mars are monitored through simultaneous measurements provided by Rosetta. Possible explanations for the asymmetries are discussed, such as crustal magnetic fields and IMF direction. In the same interval, during the high solar wind pressure pulse, MEX observations show an increased amount of escaping planetary ions from the polar region of Mars. We link the high pressure solar wind with the observed simultaneous ion outflow and discuss how the pressure pulse could also be associated with the observed boundary shape asymmetry.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
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| 41. |
- Jeppesen, H. B., et al.
(author)
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Study of Li-10 via the Li-9(H-2, p) reaction at REX-ISOLDE
- 2006
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In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 642:5-6, s. 449-454
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Journal article (peer-reviewed)abstract
- The Click to view the MathML source reaction has been investigated at 2.36 MeV/u at the REX-ISOLDE facility. In this Letter we focus on the Click to view the MathML source channel which potentially holds spectroscopic information on the unbound nucleus 10Li. The experimental excitation energy spectrum and angular distribution are compared with CCBA calculations. These calculations clearly support the existence of a low-lying (s) virtual state, with a (negative) scattering length of the order asnot, vert, similar1324 fm and a p1/2 resonance with an energy of Ersimilar, equals0.38 MeV and a width of Γsimilar, equals0.2 MeV.
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| 42. |
- Johansson, M. K., et al.
(author)
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Hematopoietic stem cell-targeted neonatal gene therapy reverses lethally progressive osteopetrosis in oc/oc mice
- 2007
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In: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 109:12, s. 5178-85
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Journal article (peer-reviewed)abstract
- Infantile malignant osteopetrosis (IMO) is a fatal disease caused by lack of functional osteoclasts, and the only available treatment is hematopoietic stem cell (HSC) transplantation. In the majority of patients, the TCIRG1 gene, coding for a subunit of a proton pump essential for bone resorption, is mutated. Oc/oc mice have a deletion in the homologue gene (tcirg1) and die at 3 to 4 weeks, but can be rescued by neonatal transplantation of HSCs. Here, HSC-targeted gene therapy of osteopetrosis in the oc/oc mouse model was developed. Oc/oc fetal liver cells depleted of Ter119-expressing erythroid cells were transduced with a retroviral vector expressing tcirg1 and GFP, and subsequently transplanted intraperitoneally to irradiated neonatal oc/oc mice. Eight of 15 mice survived past the normal life span of oc/oc mice. In vitro osteoclastogenesis revealed formation of GFP-positive osteoclasts and bone resorption, albeit at a lower level than from wild-type cells. The skeletal phenotype was analyzed by X-ray and histopathology and showed partial correction at 8 weeks and almost normalization after 18 weeks. In summary, osteopetrosis in oc/oc mice can be reversed by neonatal transplantation of gene-modified HSCs leading to long-term survival. This represents a significant step toward the development of gene therapy for osteopetrosis.
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| 43. |
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| 44. |
- Kivimäki, Antti, et al.
(author)
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Fluorescence emission following core excitations in the water molecule
- 2006
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In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 39:5, s. 1101-1112
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Journal article (peer-reviewed)abstract
- Photon-induced fluorescence spectroscopy has been used to study the fragmentation of the water molecule at the O 1s is edge. Fluorescence emission has been observed from the neutral fragments H, O and OH as well as from the ionic fragments O+ and OH+. The extracted fluorescence yields of the H Lyman-alpha emission and O 2p(3)(S-4)3p(P-3) -> 2p(3)(S-4)3s(S-3) transitions show the same structures as the total ion yield spectrum but with different relative intensities. The most intense fluorescence emission is restricted to the region of the core excitations, while above the O 1s ionization limit the signal is much weaker (in the case of H) or below the detection limit (O, OH and OH+). The fluorescence emission is concluded to follow from the following general cascade: the core-excited states decay by resonant Auger transitions, the final states reached undergo dissociation into ionic and neutral fragments, and fluorescence occurs from excited fragments. In the case of the OH (A(2)Sigma(+) -> X-2 Pi) emission, the decay of core-excited states through soft x-ray emission may also be responsible for the observed fluorescence.
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| 45. |
- Kivimäki, A., et al.
(author)
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Observation of core-hole double excitations in water using fluorescence spectroscopy
- 2007
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 75:1, s. 014503-
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Journal article (peer-reviewed)abstract
- The hydrogen Lyman-alpha, Balmer-alpha, and Balmer-beta emission has been measured from the H2O molecule at photon energies exceeding the 1s ionization threshold. Fluorescence emission is shown to be a sensitive probe to neutral core-hole doubly excited states and singly ionized 1s shake-up states that are embedded in the core ionization continuum. In addition, the photoabsorption spectrum of the water molecule in the energy range of the double excitations has been measured with better statistics than previously.
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| 46. |
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| 47. |
- Laj, P., et al.
(author)
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Measuring Atmospheric Composition Change
- 2009
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In: Atmospheric Environment. - : Elsevier BV. - 1873-2844 .- 1352-2310. ; 43:33, s. 5351-5414
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Journal article (peer-reviewed)abstract
- Scientific findings from the last decades have clearly highlighted the need for a more comprehensive approach to atmospheric change processes. In fact, observation of atmospheric composition variables has been an important activity of atmospheric research that has developed instrumental tools (advanced analytical techniques) and platforms (instrumented passenger aircrafts, ground-based in-situ and remote sensing stations, earth observation satellite instruments) providing essential information on the composition of the atmosphere. The variability of the atmospheric system and the extreme complexity of the atmospheric cycles for short-lived gaseous and aerosol species have led to the development of complex models to interpret observations, test our theoretical understanding of atmospheric chemistry and predict future atmospheric composition. The validation of numerical models requires accurate information concerning the variability of atmospheric composition for targeted species via comparison with observations and measurements. In this paper, we provide an overview of recent advances in instrumentation and methodologies for measuring atmospheric composition changes from space, aircraft and the surface as well as recent improvements in laboratory techniques that permitted scientific advance in the field of atmospheric chemistry. Emphasis is given to the most promising and innovative technologies that will become operational in the near future to improve knowledge of atmospheric composition. Our current observation capacity, however, is not satisfactory to understand and predict future atmospheric composition changes, in relation to predicted climate warming. Based on the limitation of the current European observing system, we address the major gaps in a second part of the paper to explain why further developments in current observation strategies are still needed to strengthen and optimise an observing system not only capable of responding to the requirements of atmospheric services but also to newly open scientific questions.
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| 48. |
- Malmberg, Per, 1974, et al.
(author)
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Imaging of lipids in human adipose tissue by cluster ion TOF-SIMS
- 2007
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In: Microsc Res Tech. - : Wiley. - 1059-910X .- 1097-0029. ; 70:9, s. 828-35
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Journal article (peer-reviewed)abstract
- Biopsies of human subcutaneous adipose tissue were taken from healthy donors. Samples were high-pressure frozen, freeze-fractured, and freeze dried. Imaging mass spectrometry of samples was performed in a TOF-SIMS mass spectrometer equipped with a bismuth cluster ion source. Blood vessels, the connective tissue, and adipocytes can be seen in TOF-SIMS images. Blood vessels were found labeled by a high content of sodium ions and potassium ions in their lumen and phosphocholine signal in smooth muscle cells of the vessel wall. The connective tissue showed high signal levels of CN(-) fragments, derived from proteins and nucleic acids. Adipocytes showed high signal levels of phosphocholine and cholesterol ubiquitously in their membranes and diacylglycerols in some membrane sites. The central part of adipocytes showed high levels of triacylglycerols and fatty acids. These results are in accordance to those of biochemical studies; however, a precise spatial localization of lipids in adipocytes is demonstrated with MS imaging.
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| 49. |
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| 50. |
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