| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Atwood, W. B., et al.
(författare)
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THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION
- 2009
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 697:2, s. 1071-1102
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Tidskriftsartikel (refereegranskat)abstract
- The Large Area Telescope (Fermi/LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view (FoV), high-energy gamma-ray telescope, covering the energy range from below 20 MeV to more than 300 GeV. The LAT was built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. This paper describes the LAT, its preflight expected performance, and summarizes the key science objectives that will be addressed. On-orbit performance will be presented in detail in a subsequent paper. The LAT is a pair-conversion telescope with a precision tracker and calorimeter, each consisting of a 4 x 4 array of 16 modules, a segmented anticoincidence detector that covers the tracker array, and a programmable trigger and data acquisition system. Each tracker module has a vertical stack of 18 (x, y) tracking planes, including two layers (x and y) of single-sided silicon strip detectors and high-Z converter material (tungsten) per tray. Every calorimeter module has 96 CsI(Tl) crystals, arranged in an eight-layer hodoscopic configuration with a total depth of 8.6 radiation lengths, giving both longitudinal and transverse information about the energy deposition pattern. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large FoV (2.4 sr) and ensuring that most pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. Data obtained with the LAT are intended to (1) permit rapid notification of high-energy gamma-ray bursts and transients and facilitate monitoring of variable sources, (2) yield an extensive catalog of several thousand high-energy sources obtained from an all-sky survey, (3) measure spectra from 20 MeV to more than 50 GeV for several hundred sources, (4) localize point sources to 0.3-2 arcmin, (5) map and obtain spectra of extended sources such as SNRs, molecular clouds, and nearby galaxies, (6) measure the diffuse isotropic gamma-ray background up to TeV energies, and (7) explore the discovery space for dark matter.
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| 3. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes
- 2008
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Ingår i: Autophagy. - : Landes Bioscience. - 1554-8627 .- 1554-8635. ; 4:2, s. 151-175
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Forskningsöversikt (refereegranskat)abstract
- Research in autophagy continues to accelerate,1 and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.2,3 There are many useful and convenient methods that can be used to monitor macroautophagy in yeast, but relatively few in other model systems, and there is much confusion regarding acceptable methods to measure macroautophagy in higher eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers of autophagosomes versus those that measure flux through the autophagy pathway; thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from fully functional autophagy that includes delivery to, and degradation within, lysosomes (in most higher eukaryotes) or the vacuole (in plants and fungi). Here, we present a set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes. This set of guidelines is not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to verify an autophagic response.
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| 4. |
- Clark, Andrew G., et al.
(författare)
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Evolution of genes and genomes on the Drosophila phylogeny
- 2007
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 450:7167, s. 203-218
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Tidskriftsartikel (refereegranskat)abstract
- Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species.
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| 5. |
- Band, D. L., et al.
(författare)
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Prospects for GRB Science with the Fermi Large Area Telescope
- 2009
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 701:2, s. 1673-1694
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Tidskriftsartikel (refereegranskat)abstract
- The Large Area Telescope (LAT) instrument on the Fermi mission will reveal the rich spectral and temporal gamma-ray burst (GRB) phenomena in the >100 MeV band. The synergy with Fermi's Gamma-ray Burst Monitor detectors will link these observations to those in the well explored 10-1000 keV range; the addition of the >100 MeV band observations will resolve theoretical uncertainties about burst emission in both the prompt and afterglow phases. Trigger algorithms will be applied to the LAT data both onboard the spacecraft and on the ground. The sensitivity of these triggers will differ because of the available computing resources onboard and on the ground. Here we present the LAT's burst detection methodologies and the instrument's GRB capabilities.
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| 6. |
- Angelopoulos, V., et al.
(författare)
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First Results from the THEMIS Mission
- 2008
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Ingår i: Space Science Reviews. - : Springer Science and Business Media LLC. - 0038-6308 .- 1572-9672. ; 141:1-4, s. 453-476
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Forskningsöversikt (refereegranskat)abstract
- THEMIS was launched on February 17, 2007 to determine the trigger and large-scale evolution of substorms. During the first seven months of the mission the five satellites coasted near their injection orbit to avoid differential precession in anticipation of orbit placement, which started in September 2007 and led to a commencement of the baseline mission in December 2007. During the coast phase the probes were put into a string-of-pearls configuration at 100 s of km to 2 R-E along-track separations, which provided a unique view of the magnetosphere and enabled an unprecedented dataset in anticipation of the first tail season. In this paper we describe the first THEMIS substorm observations, captured during instrument commissioning on March 23, 2007. THEMIS measured the rapid expansion of the plasma sheet at a speed that is commensurate with the simultaneous expansion of the auroras on the ground. These are the first unequivocal observations of the rapid westward expansion process in space and on the ground. Aided by the remote sensing technique at energetic particle boundaries and combined with ancillary measurements and MHD simulations, they allow determination and mapping of space currents. These measurements show the power of the THEMIS instrumentation in the tail and the radiation belts. We also present THEMIS Flux Transfer Events (FTE) observations at the magnetopause, which demonstrate the importance of multi-point observations there and the quality of the THEMIS instrumentation in that region of space.
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| 7. |
- Jones, G. H., et al.
(författare)
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The dust halo of Saturn's largest icy moon, Rhea
- 2008
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 319:5868, s. 1380-1384
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Tidskriftsartikel (refereegranskat)abstract
- Saturn's moon Rhea had been considered massive enough to retain a thin, externally generated atmosphere capable of locally affecting Saturn's magnetosphere. The Cassini spacecraft's in situ observations reveal that energetic electrons are depleted in the moon's vicinity. The absence of a substantial exosphere implies that Rhea's magnetospheric interaction region, rather than being exclusively induced by sputtered gas and its products, likely contains solid material that can absorb magnetospheric particles. Combined observations from several instruments suggest that this material is in the form of grains and boulders up to several decimetres in size and orbits Rhea as an equatorial debris disk. Within this disk may reside denser, discrete rings or arcs of material.
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| 8. |
- Schoerck, T, et al.
(författare)
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The stellar content of the Hamburg/ESO survey V. The metallicity distribution function of the Galactic halo
- 2009
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 507:2, s. 817-832
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Tidskriftsartikel (refereegranskat)abstract
- We determine the metallicity distribution function (MDF) of the Galactic halo by means of a sample of 1638 metal-poor stars selected from the Hamburg/ESO objective-prism survey (HES). The sample was corrected for minor biases introduced by the strategy for spectroscopic follow-up observations of the metal-poor candidates, namely "best and brightest stars first". Comparison of the metallicities [Fe/H] of the stars determined from moderate-resolution (i.e., R similar to 2000) follow-up spectra with results derived from abundance analyses based on high-resolution spectra (i.e., R > 20 000) shows that the [Fe/H] estimates used for the determination of the halo MDF are accurate to within 0.3 dex, once highly C-rich stars are eliminated. We determined the selection function of the HES, which must be taken into account for a proper comparison between the HES MDF with MDFs of other stellar populations or those predicted by models of Galactic chemical evolution. The latter show a reasonable agreement with the overall shape of the HES MDF for [Fe/H] > -3.6, but only a model of Salvadori et al. (2007) with a critical metallicity for low-mass star formation of Z(cr) = 10(-3.4) Z(circle dot) reproduces the sharp drop at [Fe/H] similar to -3.6 present in the HES MDF. Although currently about ten stars at [Fe/H] < -3.6 are known, the evidence for the existence of a tail of the halo MDF extending to [Fe/H] similar to -5.5 is weak from the sample considered in this paper, because it only includes two stars [Fe/H] < -3.6. Therefore, a comparison with theoretical models has to await larger statistically complete and unbiased samples. A comparison of the MDF of Galactic globular clusters and of dSph satellites to the Galaxy shows qualitative agreement with the halo MDF, derived from the HES, once the selection function of the latter is included. However, statistical tests show that the differences between these are still highly significant.
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| 9. |
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| 10. |
- Milz, Mathias, et al.
(författare)
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Validation of water vapour profiles (version 13) retrieved by the IMK/IAA scientific retrieval processor based on full resolution spectra measured by MIPAS on board Envisat
- 2009
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Ingår i: Atmospheric Measurement Techniques. - : Copernicus GmbH. - 1867-1381 .- 1867-8548. ; 2:2, s. 379-399
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Tidskriftsartikel (refereegranskat)abstract
- Vertical profiles of stratospheric water vapour measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) with the full resolution mode between September 2002 and March 2004 and retrieved with the IMK/IAA scientific retrieval processor were compared to a number of independent measurements in order to estimate the bias and to validate the existing precision estimates of the MIPAS data. The estimated precision for MIPAS is 5 to 10% in the stratosphere, depending on altitude, latitude, and season. The independent instruments were: the Halogen Occultation Experiment (HALOE), the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the Improved Limb Atmospheric Spectrometer-II (ILAS-II), the Polar Ozone and Aerosol Measurement (POAM III) instrument, the Middle Atmospheric Water Vapour Radiometer (MIAWARA), the Michelson Interferometer for Passive Atmospheric Sounding, balloon-borne version (MIPAS-B), the Airborne Microwave Stratospheric Observing System(AMSOS), the Fluorescent Stratospheric Hygrometer for Balloon (FLASH-B), the NOAA frostpoint hygrometer, and the Fast In Situ Hygrometer (FISH). For the in-situ measurements and the ground based, air- and balloon borne remote sensing instruments, the measurements are restricted to central and northern Europe. The comparisons to satellite-borne instruments are predominantly at mid- to high latitudes on both hemispheres. In the stratosphere there is no clear indicationof a bias in MIPAS data, because the independent measurements in some cases are drier and in some cases are moister than the MIPAS measurements. Compared to the infrared measurements of MIPAS, measurements in the ultraviolet and visible have a tendency to be high, whereas microwave measurements have a tendency to be low. Theresults of chi2-based precision validation are somewhat controversial among the comparison estimates. However, for comparison instruments whose error budget also includes errors due to uncertainties in spectrally interfering species and where good coincidences were found, the chi2 values found are in the expected range or even below. This suggests that there is no evidence of systematically underestimated MIPAS random errors.
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| 11. |
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| 12. |
- Gardner, J.L., et al.
(författare)
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Comparison of nighttime nitric oxide 5.3 μm emissions in the thermosphere measured by MIPAS and SABER
- 2007
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Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 112:A10
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Tidskriftsartikel (refereegranskat)abstract
- A comparative study of nitric oxide (NO) 5.3 μm emissions in the thermosphere measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) spectrometer and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) radiometer satellite instruments was conducted for nighttime data collected on 14 June 2003. The agreement between the data sets was very good, within ∼25% over the entire latitude range studied from −58° to + 4°. The MIPAS and SABER data were inverted to retrieve NO volume emission rates. Spectral fitting of the MIPAS data was used to determine the NO(v = 1) rotational and spin-orbit temperatures, which were found to be in nonlocal thermodynamic equilibrium (non-LTE) above 110 km. Near 110 km the rotational and spin-orbit temperatures converged, indicating the onset of equilibrium in agreement with the results of non-LTE modeling. Because of the onset of equilibrium the NO rotational and spin-orbit temperatures can be used to estimate the kinetic temperature near 110 km. The results indicate that the atmospheric model NRLMSISE-00 underestimates the kinetic temperature near 110 km for the locations investigated. The SABER instrument 5.3 μm band filter cuts off a significant fraction of the NO(Δv = 1) band, and therefore modeling of NO is necessary to predict the total band radiance. The needed correction factors were directly determined from the MIPAS data, providing validation of the modeled values used in SABER operational data processing. The correction factors were applied to the SABER data to calculate densities of NO(v = 1). A feasibility study was also conducted to investigate the use of NO 5.3 μm emission data to derive NO(v = 0) densities in the thermosphere.
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| 13. |
- Lynch, David K., et al.
(författare)
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NOVA V2362 CYGNI (NOVA CYGNI 2006): SPITZER, SWIFT, AND GROUND-BASED SPECTRAL EVOLUTION
- 2008
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Ingår i: Astronomical Journal. - 1538-3881 .- 0004-6256. ; 136:number 5, 2008 November, s. 1815-1827
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Tidskriftsartikel (refereegranskat)abstract
- Nova V2362 Cygni has undergone a number of very unusual changes. Ground-based spectroscopy initially revealed a normal sequence of events: the object faded and its near-infrared emission lines gradually shifted to higher excitation conditions until about day 100 when the optical fading reversed and the object slowly brightened. This was accompanied by a rise in the Swift X-ray telescope flux and a sudden shift in excitation of the visible and IR spectrum back to low levels. The new lower excitation spectrum revealed broad line widths and many P-Cygni profiles, all indicative of the ejection of a second shell. Eventually, dust formed, the X-ray brightness—apparently unaffected by dust formation—peaked and then declined, and the object faded at all wavelengths. The Spitzer dust spectra revealed a number of solid-state emission features that, at this time, are not identified.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
- Randall, C. E., et al.
(författare)
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Stratospheric effects of energetic particle precipitation in 2003-2004
- 2005
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Ingår i: Geophysical Research Letters. - 1944-8007 .- 0094-8276. ; 32:5, s. 1-4
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Tidskriftsartikel (refereegranskat)abstract
- Upper stratospheric enhancements in NOx (NO and NO2) were observed at high northern latitudes from March through at least July of 2004. Multi-satellite data analysis is used to examine the temporal evolution of the enhancements, to place them in historical context, and to investigate their origin. The enhancements were a factor of 4 higher than nominal at some locations, and are unprecedented in the northern hemisphere since at least 1985. They were accompanied by reductions in O-3 of more than 60% in some cases. The analysis suggests that energetic particle precipitation led to substantial NOx production in the upper atmosphere beginning with the remarkable solar storms in late October 2003 and possibly persisting through January. Downward transport of the excess NOx, facilitated by unique meteorological conditions in 2004 that led to an unusually strong upper stratospheric vortex from late January through March, caused the enhancements.
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| 18. |
- Remsberg, E.E., et al.
(författare)
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Assessment of the quality of the Version 1.07 temperature-versus-pressure profiles of the middle atmosphere from TIMED/SABER
- 2008
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Ingår i: Journal of Geophysical Research - Atmospheres. - 2169-897X .- 2169-8996. ; 113:D17
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Tidskriftsartikel (refereegranskat)abstract
- The quality of the retrieved temperature-versus-pressure (or T(p)) profiles is described for the middle atmosphere for the publicly available Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) Version 1.07 (V1.07) data set. The primary sources of systematic error for the SABER results below about 70 km are (1) errors in the measured radiances, (2) biases in the forward model, and (3) uncertainties in the corrections for ozone and in the determination of the reference pressure for the retrieved profiles. Comparisons with other correlative data sets indicate that SABER T(p) is too high by 1–3 K in the lower stratosphere but then too low by 1 K near the stratopause and by 2 K in the middle mesosphere. There is little difference between the local thermodynamic equilibrium (LTE) algorithm results below about 70 km from V1.07 and V1.06, but there are substantial improvements/differences for the non-LTE results of V1.07 for the upper mesosphere and lower thermosphere (UMLT) region. In particular, the V1.07 algorithm uses monthly, diurnally averaged CO2 profiles versus latitude from the Whole Atmosphere Community Climate Model. This change has improved the consistency of the character of the tides in its kinetic temperature (Tk). The Tk profiles agree with UMLT values obtained from ground-based measurements of column-averaged OH and O2 emissions and of the Na lidar returns, at least within their mutual uncertainties. SABER Tk values obtained near the mesopause with its daytime algorithm also agree well with the falling sphere climatology at high northern latitudes in summer. It is concluded that the SABER data set can be the basis for improved, diurnal-to-interannual-scale temperatures for the middle atmosphere and especially for its UMLT region.
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| 19. |
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| 20. |
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| 21. |
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| 22. |
- Allwood, J. M., et al.
(författare)
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An approach to scenario analysis of the sustainability of an industrial sector applied to clothing and textiles in the UK
- 2008
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 16:12, s. 1234-1246
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Tidskriftsartikel (refereegranskat)abstract
- Companies aiming to be 'sustainability leaders' in their sector and governments wanting to support their ambitions need a means to assess the changes required to make a significant difference in the impact of their whole sector. Previous work on scenario analysis/scenario planning demonstrates extensive developments and applications, but as yet few attempts to integrate the 'triple bottom line' concerns of sustainability into scenario planning exercises. This paper, therefore, presents a methodology for scenario analysis of large change to an entire sector. The approach includes calculation of a 'triple bottom line graphic equaliser' to allow exploration and evaluation of the trade-offs between economic, environmental and social impacts. The methodology is applied to the UK's clothing and textiles sector, and results from the study of the sector are summarised. In reflecting on the specific study, some suggestions are made about future application of a similar methodology, including a template of candidate solutions that may lead to significant reduction in impacts.
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| 23. |
- Kroepelin, S, et al.
(författare)
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Climate-driven ecosystem succession in the Sahara: The past 6000 years
- 2008
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 320:5877, s. 765-768
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Tidskriftsartikel (refereegranskat)abstract
- Desiccation of the Sahara since the middle Holocene has eradicated all but a few natural archives recording its transition from a "green Sahara" to the present hyperarid desert. Our continuous 6000- year paleoenvironmental reconstruction from northern Chad shows progressive drying of the regional terrestrial ecosystem in response to weakening insolation forcing of the African monsoon and abrupt hydrological change in the local aquatic ecosystem controlled by site- specific thresholds. Strong reductions in tropical trees and then Sahelian grassland cover allowed large- scale dust mobilization from 4300 calendar years before the present ( cal yr B. P.). Today's desert ecosystem and regional wind regime were established around 2700 cal yr B. P. This gradual rather than abrupt termination of the African Humid Period in the eastern Sahara suggests a relatively weak biogeophysical feedback on climate.
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| 24. |
- Clutton-Brock, T. H., et al.
(författare)
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Intrasexual competition and sexual selection in cooperative mammals
- 2006
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 444:7122, s. 1065-1068
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Tidskriftsartikel (refereegranskat)abstract
- In most animals, the sex that invests least in its offspring competes more intensely for access to the opposite sex and shows greater development of secondary sexual characters than the sex that invests most(1,2). However, in some mammals where females are the primary care-givers, females compete more frequently or intensely with each other than males(3-5). A possible explanation is that, in these species, the resources necessary for successful female reproduction are heavily concentrated and intrasexual competition for breeding opportunities is more intense among females than among males. Intrasexual competition between females is likely to be particularly intense in cooperative breeders where a single female monopolizes reproduction in each group(6). Here, we use data from a twelve-year study of wild meerkats (Suricata suricatta), where females show high levels of reproductive skew, to show that females gain greater benefits from acquiring dominant status than males and traits that increase competitive ability exert a stronger influence on their breeding success. Females that acquire dominant status also develop a suite of morphological, physiological and behavioural characteristics that help them to control other group members. Our results show that sex differences in parental investment are not the only mechanism capable of generating sex differences in reproductive competition and emphasize the extent to which competition for breeding opportunities between females can affect the evolution of sex differences and the operation of sexual selection.
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| 25. |
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| 26. |
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| 27. |
- Ma, Li-Jun, et al.
(författare)
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Genomic analysis of the basal lineage fungus Rhizopus oryzae reveals a whole-genome duplication.
- 2009
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Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 5:7, s. e1000549-
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Tidskriftsartikel (refereegranskat)abstract
- Rhizopus oryzae is the primary cause of mucormycosis, an emerging, life-threatening infection characterized by rapid angioinvasive growth with an overall mortality rate that exceeds 50%. As a representative of the paraphyletic basal group of the fungal kingdom called "zygomycetes," R. oryzae is also used as a model to study fungal evolution. Here we report the genome sequence of R. oryzae strain 99-880, isolated from a fatal case of mucormycosis. The highly repetitive 45.3 Mb genome assembly contains abundant transposable elements (TEs), comprising approximately 20% of the genome. We predicted 13,895 protein-coding genes not overlapping TEs, many of which are paralogous gene pairs. The order and genomic arrangement of the duplicated gene pairs and their common phylogenetic origin provide evidence for an ancestral whole-genome duplication (WGD) event. The WGD resulted in the duplication of nearly all subunits of the protein complexes associated with respiratory electron transport chains, the V-ATPase, and the ubiquitin-proteasome systems. The WGD, together with recent gene duplications, resulted in the expansion of multiple gene families related to cell growth and signal transduction, as well as secreted aspartic protease and subtilase protein families, which are known fungal virulence factors. The duplication of the ergosterol biosynthetic pathway, especially the major azole target, lanosterol 14alpha-demethylase (ERG11), could contribute to the variable responses of R. oryzae to different azole drugs, including voriconazole and posaconazole. Expanded families of cell-wall synthesis enzymes, essential for fungal cell integrity but absent in mammalian hosts, reveal potential targets for novel and R. oryzae-specific diagnostic and therapeutic treatments.
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| 28. |
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| 29. |
- Ringden, O, et al.
(författare)
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The graft-versus-leukemia effect using matched unrelated donors is not superior to HLA-identical siblings for hematopoietic stem cell transplantation
- 2009
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 113:13, s. 3110-3118
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Tidskriftsartikel (refereegranskat)abstract
- Do some patients benefit from an unrelated donor (URD) transplant because of a stronger graft-versus-leukemia (GVL) effect? We analyzed 4099 patients with acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic myeloid leukemia (CML) undergoing a myeloablative allogeneic hematopoietic cell transplantation (HCT) from an URD (8/8 human leukocyte antigen [HLA]–matched, n = 941) or HLA-identical sibling donor (n = 3158) between 1995 and 2004 reported to the CIBMTR. In the Cox regression model, acute and chronic GVHD were added as time-dependent variables. In multivariate analysis, URD transplant recipients had a higher risk for transplantation-related mortality (TRM; relative risk [RR], 2.76; P < .001) and relapse (RR, 1.50; P < .002) in patients with AML, but not ALL or CML. Chronic GVHD was associated with a lower relapse risk in all diagnoses. Leukemia-free survival (LFS) was decreased in patients with AML without acute GVHD receiving a URD transplant (RR, 2.02; P < .001) but was comparable to those receiving HLA-identical sibling transplants in patients with ALL and CML. In patients without GVHD, multivariate analysis showed similar risk of relapse but decreased LFS for URD transplants for all 3 diagnoses. In conclusion, risk of relapse was the same (ALL, CML) or worse (AML) in URD transplant recipients compared with HLA-identical sibling transplant recipients, suggesting a similar GVL effect.
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| 30. |
- Steck, T., et al.
(författare)
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Bias determination and precision validation of ozone profiles from MIPAS-Envisat retrieved with the IMK-IAA processor
- 2007
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Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 7:13, s. 3639-3662
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Tidskriftsartikel (refereegranskat)abstract
- This paper characterizes vertical ozone profiles retrieved with the IMK-IAA (Institute for Meteorology and Climate Research, Karlsruhe – Instituto de Astrofisica de Andalucia) science-oriented processor from high spectral resolution data (until March 2004) measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) aboard the environmental satellite Envisat. Bias determination and precision validation is performed on the basis of correlative measurements by ground-based lidars, Fourier transform infrared spectrometers, and microwave radiometers as well as balloon-borne ozonesondes, the balloon-borne version of MIPAS, and two satellite instruments (Halogen Occultation Experiment and Polar Ozone and Aerosol Measurement III). Percentage mean differences between MIPAS and the comparison instruments for stratospheric ozone are generally within ±10%. The precision in this altitude region is estimated at values between 5 and 10% which gives an accuracy of 15 to 20%. Below 18 km, the spread of the percentage mean differences is larger and the precision degrades to values of more than 20% depending on altitude and latitude. The main reason for the degraded precision at low altitudes is attributed to undetected thin clouds which affect MIPAS retrievals, and to the influence of uncertainties in the water vapor concentration.
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| 31. |
- Wang, D.Y., et al.
(författare)
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Comparisons of MIPAS/ENVISAT ozone profiles with SMR/ODIN and HALOE/UARS observations
- 2005
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Ingår i: Advances in Space Research. - : Elsevier BV. - 1879-1948 .- 0273-1177. ; 36:5, s. 927-931
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Tidskriftsartikel (refereegranskat)abstract
- Ozone volume mixing ratio (VMR) profiles are measured by the Michelson Interferometer for passive atmospheric sounding (MIPAS) on ENVISAT. The data sets produced by the science data processor at Institut fur Meteorologic und Klimaforschung (IMK), Germany are compared with those obtained by halogen occultation experiment (HALOE) on UARS and by sub-millimetre radiometer (SMR) on ODIN. For the stratospheric measurements taken during September/October 2002, the three instruments show reasonable agreement, with global mean differences within 0.1-0.3 ppmv. The typical zonal mean differences are of 0.4 ppmv for HALOE and 0.6 ppmv for SMR (4-6%) in the ozone VMR peak region at 25-30 km near the equator, though larger differences of 0.8-1 ppmv (8-10%) are also observed in a small latitude-altitude region in the tropic. A positive bias of about 0.2-0.4 ppmv in the MIPAS data in the 35-40 km region has also been found. Further studies are under way to explain these differences.
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| 32. |
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