| 1. |
- Schael, S, et al.
(författare)
-
Precision electroweak measurements on the Z resonance
- 2006
-
Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
-
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.
|
|
| 2. |
- Abate, E., et al.
(författare)
-
Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors
- 2008
-
Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
-
Tidskriftsartikel (refereegranskat)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.
|
|
| 3. |
|
|
| 4. |
- Meyer, H., et al.
(författare)
-
Overview of physics results from MAST
- 2009
-
Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 49:10, s. 104017-
-
Tidskriftsartikel (refereegranskat)abstract
- Several improvements to the MAST plant and diagnostics have facilitated new studies advancing the physics basis for ITER and DEMO, as well as for future spherical tokamaks (STs). Using the increased heating capabilities P-NBI <= 3.8 MW H-mode at I-P = 1.2 MA was accessed showing that the energy confinement on MAST scales more weakly with I-P and more strongly with B-t than in the ITER IPB98(y, 2) scaling. Measurements of the fuel retention of shallow pellets extrapolate to an ITER particle throughput of 70% of its original designed total throughput capacity. The anomalous momentum diffusion, chi(phi), is linked to the ion diffusion, chi(i), with a Prandtl number close to P-phi approximate to chi(phi)/chi(i) approximate to 1, although chi(i) approaches neoclassical values. New high spatial resolution measurements of the edge radial electric field, E-r, show that the position of steepest gradients in electron pressure and E-r (i.e. shearing rate) are coincident, but their magnitudes are not linked. The T-e pedestal width on MAST scales with root beta(ped)(pol) rather than rho(pol). The edge localized mode (ELM) frequency for type-IV ELMs, new in MAST, was almost doubled using n = 2 resonant magnetic perturbations from a set of four external coils (n = 1, 2). A new internal 12 coil set (n <= 3) has been commissioned. The filaments in the inter-ELM and L-mode phase are different from ELM filaments, and the characteristics in L-mode agree well with turbulence calculations. A variety of fast particle driven instabilities were studied from 10 kHz saturated fishbone like activity up to 3.8 MHz compressional Alfven eigenmodes. Fast particle instabilities also affect the off-axis NBI current drive, leading to fast ion diffusion of the order of 0.5 m(2) s(-1) and a reduction in the driven current fraction from 40% to 30%. EBW current drive start-up is demonstrated for the first time in a ST generating plasma currents up to 55 kA. Many of these studies contributed to the physics basis of a planned upgrade to MAST.
|
|
| 5. |
- Lloyd, B., et al.
(författare)
-
Overview of physics results from MAST
- 2007
-
Ingår i: Nuclear Fusion. - 0029-5515 .- 1741-4326. ; 47:10, s. S658-S667
-
Tidskriftsartikel (refereegranskat)abstract
- Substantial advances have been made on the Mega AmpÚre Spherical Tokamak (MAST). The parameter range of the MAST confinement database has been extended and it now also includes pellet-fuelled discharges. Good pellet retention has been observed in H-mode discharges without triggering an ELM or an H/L transition during peripheral ablation of low speed pellets. Co-ordinated studies on MAST and DIII-D demonstrate a strong link between the aspect ratio and the beta scaling of H-mode energy confinement, consistent with that obtained when MAST data were merged with a subset of the ITPA database. Electron and ion ITBs are readily formed and their evolution has been investigated. Electron and ion thermal diffusivities have been reduced to values close to the ion neoclassical level. Error field correction coils have been used to determine the locked mode threshold scaling which is comparable to that in conventional aspect ratio tokamaks. The impact of plasma rotation on sawteeth has been investigated and the results have been well-modelled using the MISHKA-F code. Alfvén cascades have been observed in discharges with reversed magnetic shear. Measurements during off-axis NBCD and heating are consistent with classical fast ion modelling and indicate efficient heating and significant driven current. Central electron Bernstein wave heating has been observed via the O-X-B mode conversion process in special magnetically compressed plasmas. Plasmas with low pedestal collisionality have been established and further insight has been gained into the characteristics of filamentary structures at the plasma edge. Complex behaviour of the divertor power loading during plasma disruptions has been revealed by high resolution infra-red measurements.
|
|
| 6. |
- Clark, Andrew G., et al.
(författare)
-
Evolution of genes and genomes on the Drosophila phylogeny
- 2007
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 450:7167, s. 203-218
-
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.
|
|
| 7. |
- Jégou, F., et al.
(författare)
-
Validation of Odin/SMR limb observations of ozone, comparisons with OSIRIS, POAM III, ground-based and balloon-borne intruments
- 2008
-
Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 8:13, s. 3385-3409
-
Tidskriftsartikel (refereegranskat)abstract
- The Odin satellite carries two instruments capable of determining stratospheric ozone profiles by limb sounding: the Sub-Millimetre Radiometer (SMR) and the UV-visible spectrograph of the OSIRIS (Optical Spectrograph and InfraRed Imager System) instrument. A large number of ozone profiles measurements were performed during six years from November 2001 to present. This ozone dataset is here used to make quantitative comparisons with satellite measurements in order to assess the quality of the Odin/SMR ozone measurements. In a first step, we compare Swedish SMR retrievals version 2.1, French SMR ozone retrievals version 222 (both from the 501.8 GHz band), and the OSIRIS retrievals version 3.0, with the operational version 4.0 ozone product from POAM III (Polar Ozone Atmospheric Measurement). In a second step, we refine the Odin/SMR validation by comparisons with ground-based instruments and balloon-borne observations. We use observations carried out within the framework of the Network for Detection of Atmospheric Composition Change (NDACC) and balloon flight missions conducted by the Canadian Space Agency (CSA), the Laboratoire de Physique et de Chimie de l\'{}Environnement (LPCE, Orléans, France), and the Service d'Aéronomie (SA, Paris, France). Coincidence criteria were 5° in latitude×10° in longitude, and 5 h in time in Odin/POAM III comparisons, 12 h in Odin/NDACC comparisons, and 72 h in Odin/balloons comparisons. An agreement is found with the POAM III experiment (10–60 km) within −0.3±0.2 ppmv (bias±standard deviation) for SMR (v222, v2.1) and within −0.5±0.2 ppmv for OSIRIS (v3.0). Odin ozone mixing ratio products are systematically slightly lower than the POAM III data and show an ozone maximum lower by 1–5 km in altitude. The comparisons with the NDACC data (10–34 km for ozonesonde, 10–50 km for lidar, 10–60 for microwave instruments) yield a good agreement within −0.15±0.3 ppmv for the SMR data and −0.3±0.3 ppmv for the OSIRIS data. Finally the comparisons with instruments on large balloons (10–31 km) show a good agreement, within −0.7±1 ppmv. The official SMR v2.1 dataset is consistent in all altitude ranges with POAM III, NDACC and large balloon-borne instruments measurements. In the SMR v2.1 data, no different systematic error has been found in the 0–35km range in comparison with the 35–60 km range. The same feature has been highlighted in both hemispheres in SMR v2.1/POAM III intercomparisons, and no latitudinal dependence has been revealed in SMR v2.1/NDACC intercomparisons.
|
|
| 8. |
|
|
| 9. |
- Merbold, L., et al.
(författare)
-
Precipitation as driver of carbon fluxes in 11 African ecosystems
- 2009
-
Ingår i: Biogeosciences. - 1726-4189. ; 6:6, s. 1027-1041
-
Tidskriftsartikel (refereegranskat)abstract
- This study reports carbon and water fluxes between the land surface and atmosphere in eleven different ecosystems types in Sub-Saharan Africa, as measured using eddy covariance (EC) technology in the first two years of the CarboAfrica network operation. The ecosystems for which data were available ranged in mean annual rainfall from 320 mm (Sudan) to 1150 mm (Republic of Congo) and include a spectrum of vegetation types (or land cover) (open savannas, woodlands, croplands and grasslands). Given the shortness of the record, the EC data were analysed across the network rather than longitudinally at sites, in order to understand the driving factors for ecosystem respiration and carbon assimilation, and to reveal the different water use strategies in these highly seasonal environments. Values for maximum net carbon assimilation rates (photosynthesis) ranged from -12.5 mu mol CO2 m(-2) s(-1) in a dry, open Millet cropland (C-4-plants) up to -48 mu mol CO2 m(-2) s(-1) for a tropical moist grassland. Maximum carbon assimilation rates were highly correlated with mean annual rainfall (r(2)=0.74). Maximum photosynthetic uptake rates (Fp(max)) were positively related to satellite-derived f(APAR). Ecosystem respiration was dependent on temperature at all sites, and was additionally dependent on soil water content at sites receiving less than 1000 mm of rain per year. All included ecosystems dominated by C-3-plants, showed a strong decrease in 30-min assimilation rates with increasing water vapour pressure deficit above 2.0 kPa.
|
|
| 10. |
- Lloyd-Spets, Anita, 1951-, et al.
(författare)
-
Thermal detection mechanism of SiC based hydrogen resistive gas sensors
- 2006
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 89:18
-
Tidskriftsartikel (refereegranskat)abstract
- Silicon carbide (SiC) resistive hydrogen gas sensors have been fabricated and tested. Planar NiCr contacts were deposited on a thin 3C-SiC epitaxial film grown on thin Si wafers bonded to polycrystalline SiC substrates. At 673 K, up to a 51.75±0.04% change in sensor output current and a change in the device temperature of up to 163.1±0.4 K were demonstrated in response to 100% H2 in N2. Changes in device temperature are shown to be driven by the transfer of heat from the device to the gas, giving rise to a thermal detection mechanism. © 2006 American Institute of Physics.
|
|
| 11. |
- Yin, Beatrice W T, et al.
(författare)
-
Monoclonal antibody MX35 detects the membrane transporter NaPi2b (SLC34A2) in human carcinomas
- 2008
-
Ingår i: Cancer Immunity. - 1424-9634. ; 8, s. 3-
-
Tidskriftsartikel (refereegranskat)abstract
- Mouse monoclonal antibody MX35 was developed against ovarian cancer. The antibody showed homogeneous reactivity with approximately 90% of human ovarian epithelial cancers and with a limited number of normal tissues by immunohistochemistry. Although mAb MX35 has been used in a number of clinical trials in ovarian cancer, it has been difficult to define the molecular identity of MX35. We report here that mAb MX35 recognizes the sodium-dependent phosphate transport protein 2b (NaPi2b) in human cancer cells. This conclusion is based on several lines of experimental evidence, including 1) the identification of SLC34A2, the gene coding for NaPi2b, by immunoscreening an ovarian cancer cell line cDNA expression library with mAb MX35; 2) mass spectrometry sequencing of peptides obtained by fragmentation from mAb MX35 affinity-purified antigen, which show complete sequence homology to amino acid sequences in NaPi2b; 3) selective down-regulation of SLC34A2 gene expression by RNA interference and the resulting loss of mAb MX35 binding to MX35-expressing human cancer cells; and 4) the demonstration of specific mAb MX35 reactivity with recombinant fusion proteins and with synthetic peptides of the putative largest extracellular loop of NaPi2b. We further show that NaPi2b in cancer cells is expressed on the cell surface as a heavily N-glycosylated protein, with evidence of additional post-translational modifications such as palmitoylation and the formation of disulfide bridges in the major extracellular loop. Membrane transporter molecules, such as NaPi2b, represent a new family of potential cell surface targets for the immunotherapy of cancer with monoclonal antibodies.
|
|
| 12. |
- Campbell, JD, et al.
(författare)
-
Peptide immunotherapy in allergic asthma generates IL-10-dependent immunological tolerance associated with linked epitope suppression
- 2009
-
Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 206:7, s. 1535-1547
-
Tidskriftsartikel (refereegranskat)abstract
- Treatment of patients with allergic asthma using low doses of peptides containing T cell epitopes from Fel d 1, the major cat allergen, reduces allergic sensitization and improves surrogate markers of disease. Here, we demonstrate a key immunological mechanism, linked epitope suppression, associated with this therapeutic effect. Treatment with selected epitopes from a single allergen resulted in suppression of responses to other (“linked”) epitopes within the same molecule. This phenomenon was induced after peptide immunotherapy in human asthmatic subjects and in a novel HLA-DR1 transgenic mouse model of asthma. Tracking of allergen-specific T cells using DR1 tetramers determined that suppression was associated with the induction of interleukin (IL)-10+ T cells that were more abundant than T cells specific for the single-treatment peptide and was reversed by anti–IL-10 receptor administration. Resolution of airway pathophysiology in this model was associated with reduced recruitment, proliferation, and effector function of allergen-specific Th2 cells. Our results provide, for the first time, in vivo evidence of linked epitope suppression and IL-10 induction in both human allergic disease and a mouse model designed to closely mimic peptide therapy in humans.
|
|
| 13. |
|
|
| 14. |
- Lloyd-Spets, Anita, 1951-, et al.
(författare)
-
Shear mode AlN thin film electroacoustic resonator for biosensor applications
- 2005
-
Ingår i: IEEE Sensors 2005,2005. ; , s. 492-
-
Konferensbidrag (refereegranskat)abstract
- A thin film thickness excited shear acoustic wave resonator is presented. Utilizing a newly developed reactive sputtering process AlN thin films with inclined c-axis relative to the surface normal with a mean tilt of around 30deg are successfully grown. Using the above process, a biosensor consisting of a shear mode thin film bulk acoustic resonator (FBAR) and a microfluidic transport system was fabricated. The biosensor operation in water, glycerol and albumin was characterized. The resonator had a resonance frequency of around 1.2 GHz and a Q value in water of around 150. Results concerning the stability and resolution are also presented. The results demonstrate clearly the potential of FBAR biosensors for the fabrication of highly sensitive low cost biosensors, bioanalytical tools as well as for liquid sensing in general
|
|
| 15. |
- Mantlana, K. B., et al.
(författare)
-
Biomass and leaf-level gas exchange characteristics of three African savanna C-4 grass species under optimum growth conditions
- 2009
-
Ingår i: African Journal of Ecology. - : Wiley. - 1365-2028 .- 0141-6707. ; 47:4, s. 482-489
-
Tidskriftsartikel (refereegranskat)abstract
- C-4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration and leaf-to-air vapour pressure deficit gradient (D-l). Digitaria eriantha showed the largest above- and below-ground biomass, high efficiency in carbon gain under light-limiting conditions, high water use efficiency (WUE) and strong stomatal sensitivity to D-l (P = 0.002; r2 = 0.5). Panicum repens had a high aboveground biomass and attained high light saturated photosynthetic rates (A(sat), 47 mu mol m-2 s-1), stomatal conductance, (g(sat), 0.25 mol m-2 s-1) at relatively high WUE. Eragrostis lehmanniana had almost half the biomass of other species, and had similar A(sat) and g(sat) but were attained at lower WUE than the other species. This species also showed the weakest stomatal response to D-l (P = 0.19, r2 = 0. 1). The potential ecological significance of the contrasting patterns of biomass allocation and variations in gas exchange parameters among the species are discussed.Resume On a fait pousser des especes herbeuses de savane de type C4, Digitaria eriantha, Eragrostis lehmanniana et Panicum repens, dans des conditions optimales dans le but de caracteriser l'allocation de leur biomasse aerienne et racinaire et la reponse de leur echange gazeux des changements d'intensite de la lumiere, de concentrations de CO2, et un gradient deficitaire (D-l) de pression de vapeur feuille-air. D. eriantha montrait la plus grande biomasse aerienne et racinaire, une grande efficience de l'assimilation de carbone dans des conditions de luminosite limitee, une grande efficience d'utilisation de l'eau (WUE) et une forte sensibilite des stomates D-l (P = 0,002; r2 = 0,5). P. repens avait une grande biomasse aerienne et atteignait des taux photosynthetiques eleves en lumiere saturee (A(sat), 47 mu mol m-2 s-1), et une conductance stomatique (g(sat) 0.25 mol m-2 s-1) une WUE relativement elevee. E. lehmanniana avait une biomasse qui etait presque la moitie de celle des autres especes et avait un A(sat) et un g(sat) similaires mais qui etaient atteints une WUE plus basse que les autres especes. Cette espece montrait aussi la plus faible reponse stomatique D-l (P = 0,19, r2 = 0,1). L'on discute de la signification ecologique potentielle de ces schemas contrastes d'allocations de biomasse et des variations des parametres des echanges gazeux entre les especes.
|
|
| 16. |
- Mantlana, K. B., et al.
(författare)
-
Photosynthetic properties of C-4 plants growing in an African savanna/wetland mosaic
- 2008
-
Ingår i: Journal of Experimental Botany. - : Oxford University Press (OUP). - 0022-0957 .- 1460-2431. ; 59:14, s. 3941-3952
-
Tidskriftsartikel (refereegranskat)abstract
- Photosynthesis rates and photosynthesis-leaf nutrient relationships were analysed in nine tropical grass and sedge species growing in three different ecosystems: a rain-fed grassland, a seasonal floodplain, and a permanent swamp, located along a hydrological gradient in the Okavango Delta, Botswana. These investigations were conducted during the rainy season, at a time of the year when differences in growth conditions between the sites were relatively uniform. At the permanent swamp, the largest variations were found for area-based leaf nitrogen contents, from 20 mmol m(-2) to 140 mmol m(-2), nitrogen use efficiencies (NUE), from 0.2 mmol (C) mol(-1) (N) s(-1) to 2.0 mmol (C) mol(-1) (N) s(-1), and specific leaf areas (SLA), from 50 cm(2) g(-1) to 400 cm(2) g(-1). For the vegetation growing at the rainfed grassland, the highest leaf gas exchange rates, high leaf nutrient levels, a low ratio of intercellular to ambient CO2 concentration, and high carboxylation efficiency were found. Taken together, these observations indicate a very efficient growth strategy that is required for survival and reproduction during the relatively brief period of water availability. The overall lowest values of light-saturated photosynthesis (A(sat)) were observed at the seasonal floodplain; around 25 mu mol m(-2) s(-1) and 30 mu mol m(-2) s(-1). To place these observations into the broader context of functional leaf trait analysis, relationships of photosynthesis rates, specific leaf area, and foliar nutrient levels were plotted, in the same way as was done for previously published 'scaling relationships' that are based largely on C-3 plants, noting the differences in the analyses between this study and the previous study. The within-and across-species variation in both A(sat) and SLA appeared better predicted by foliar phosphorus content (dry mass or area basis) rather than by foliar nitrogen concentrations, possibly because the availability of phosphorus is even more critical than the availability of nitrogen in the studied relatively oligotrophic ecosystems.
|
|
| 17. |
- Mantlana, K B, et al.
(författare)
-
Seasonal and inter-annual photosynthetic response of representative C-4 species to soil water content and leaf nitrogen concentration across a tropical seasonal floodplain
- 2008
-
Ingår i: Journal of Tropical Ecology. - 0266-4674. ; 24, s. 201-213
-
Tidskriftsartikel (refereegranskat)abstract
- We examined the seasonal and inter-annual variation of leaf-level photosynthetic characteristics of three C-4 perennial species, Cyperus articulatus, Panicum repens and Imperata cylindrica, and their response to environmental variables, to determine comparative physiological responses of plants representing particular microhabitats within a seasonal tropical floodplain in the Okavango River Delta, Botswana. Five measurement campaigns were carried out over a period of 2 y which covered two early rainy seasons, two late rainy seasons and one dry season. For all three species, light-saturated net photosynthetic rates (A(sat)) and stomatal conductance (9,at) decreased with decreasing soil water content with a seasonal range for A(sat) of approximately 5-45 mu mol m(-2) s(-1), and for g(sat) of 0.03-0.35 mol m-2 s(-1). The species representing the wettest microhabitat (Cyperus) had the highest g(sat) at low leaf-to-air vapour pressure deficits (D-l), the highest ratio of intercellular to ambient CO2 concentration (C-i/C-a), as well as the highest degree of variation in C-l/C-a from season to season. We interpret this as being indicative of its adaptation to a moist growth environment allowing for non-conservative water use strategies as soil moisture is usually abundant. For all three species there was significant variation in photosynthetic fluxes from one year to another that was related to variation in leaf nitrogen and phosphorus. This study shows that when assessing the role of savanna stands in large-scale carbon balance models, the remarkable inter-annual variation in leaf photosynthesis reported in this study should be taken into account.
|
|
| 18. |
|
|
| 19. |
- Sioris, C. E., et al.
(författare)
-
Vertical profiles of lightning-produced NO2 enhancements in the upper troposphere observed by OSIRIS
- 2007
-
Ingår i: Atmospheric Chemistry and Physics. - 1680-7316 .- 1680-7324. ; 7:16, s. 4281-4294
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study is to perform a global search of the upper troposphere (z >= 10 km) for enhancements of nitrogen dioxide and determine their sources. This is the first application of satellite-based limb scattering to study upper tropospheric NO2. We have searched two years ( May 2003 - May 2005) of OSIRIS ( Optical Spectrograph and Infrared Imager System) operational NO2concentrations ( version 2.3/ 2.4) to find large enhancements in the observations by comparing with photochemical box model calculations and by identifying local maxima in NO2 volume mixing ratio. We find that lightning is the main production mechanism responsible for the large enhancements in OSIRIS NO2 observations as expected. Similar patterns in the abundances and spatial distribution of the NO2 enhancements are obtained by perturbing the lightning within the GEOS- Chem 3- dimensional chemical transport model. In most cases, the presence of lightning is confirmed with coincident imagery from LIS ( Lightning Imaging Sensor) and the spatial extent of the NO2 enhancement is mapped using nadir observations of tropospheric NO2 at high spatial resolution from SCIAMACHY ( Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) and OMI ( Ozone Monitoring Instrument). The combination of the lightning and chemical sensors allows us to investigate globally the role of lightning to the abundance of NO2 in the upper troposphere ( UT). Lightning contributes 60% of the tropical upper tropospheric NO2 in GEOS- Chem simulations. The spatial and temporal distribution of NO2 enhancements from lightning ( Maylyzed.
|
|
| 20. |
- Skibinski, G, et al.
(författare)
-
Mutations in the endosomal ESCRTIII-complex subunit CHMP2B in frontotemporal dementia
- 2005
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 37:8, s. 806-808
-
Tidskriftsartikel (refereegranskat)abstract
- We have previously reported a large Danish pedigree with autosomal dominant frontotemporal dementia (FTD) linked to chromosome 3 (FTD3). Here we identify a mutation in CHMP2B, encoding a component of the endosomal ESCRTIII complex, and show that it results in aberrant mRNA splicing in tissue samples from affected members of this family. We also describe an additional missense mutation in an unrelated individual with FTD. Aberration in the endosomal ESCRTIII complex may result in FTD and neurodegenerative disease.
|
|
| 21. |
|
|
| 22. |
- Wasteson, Elisabet, et al.
(författare)
-
Depression assessment and classification in palliative cancer patients : a systematic literature review
- 2009
-
Ingår i: Palliative Medicine. - : SAGE Publications. - 0269-2163 .- 1477-030X. ; 23:8, s. 739-753
-
Forskningsöversikt (refereegranskat)abstract
- The objective of this study was to review the literature on depression in palliative cancer care in order to identify which assessment methods and classification systems have been used in studies of depression. Extensive electronic database searches in PubMed, CancerLit, CINAHL, PsychINFO, EMBASE and AgeLine as well as hand search were carried out. In the 202 included papers, 106 different assessment methods were used. Sixty-five of these were only used once. All together, the Hospital Anxiety and Depression Scale ( HADS) was the most commonly used assessment method. However, there were regional differences and while the HADS dominated in Europe it was quite seldom used in Canada or in the USA. Few prevalence and intervention studies used assessment methods with an explicit reference to a diagnostic system. There were in total few case definitions of depression. Among these, the classifications were in general based on cut-off scores (77%) and not according to diagnostic systems. The full range of the DSM-IV diagnostic criteria was seldom assessed, i.e. less than one-third of the assessments in the review took into account the duration of symptoms and 18% assessed consequences and impact upon patient functioning. A diversity of assessment methods had been used. Few studies classified depression by referring to a diagnostic system or by using cut-off scores. Evidently, there is a need for a consensus on how to assess and conceptualize depression and related conditions in palliative care.
|
|
| 23. |
- Wingbrant, Helena, et al.
(författare)
-
Co-sputtered metal and SiO2 layers for use in thick-film MISiC NH3 sensors
- 2006
-
Ingår i: IEEE Sensors Journal. - 1530-437X. ; 6:4, s. 887-897
-
Tidskriftsartikel (refereegranskat)abstract
- High-temperature metal-insulator-silicon-carbide (MISiC) sensors are currently under development for use as NH3 sensors in selective-catalytic-reduction (SCR) systems in diesel engines or non-SCR (NSCR) systems in boilers. The detection of NH3 by these sensors requires the presence of triple points where the gas, the metal, and the insulator meet. These triple points have traditionally been located at the interface between the insulator and a porous metal. However, to facilitate the long-term stability of the devices when used in a harsh environment, a nonporous gate material would be preferred. Here, the behavior of the samples where such triple points have been introduced in a dense film through cosputtering of the insulator (SiO 2), and either Pt or Ir is studied. The NH3 sensitivity of the materials was found to be in accordance with the earlier investigations on Si-based samples with cosputtered gate materials. Several metal-to-insulator ratios for each of the metals Pt and Ir were studied. The sensitivity of the layers as well as their selectivity to different concentrations of NH3 at temperatures ranging from 150 degC to 450 degC was investigated. The films containing 60%-70% Pt or Ir were found to give a high sensitivity toward NH3. These samples were shown to be sensitive also to propylene and H2 but were rather insensitive to NO and CO.
|
|
