| 1. |
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| 2. |
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| 3. |
- Abdesselam, A., et al.
(författare)
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Engineering for the ATLAS SemiConductor Tracker (SCT) end-cap
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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Tidskriftsartikel (refereegranskat)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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| 4. |
- Abate, E., et al.
(författare)
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Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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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.
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| 5. |
- Abdesselam, A., et al.
(författare)
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The ATLAS semiconductor tracker end-cap module
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 575:3, s. 353-389
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Tidskriftsartikel (refereegranskat)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.
(författare)
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The barrel modules of the ATLAS semiconductor tracker
- 2006
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 568:2, s. 642-671
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Tidskriftsartikel (refereegranskat)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. |
- Emerging Risk Factors, Collaboration, et al.
(författare)
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The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases
- 2007
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Ingår i: Eur J Epidemiol. - 0393-2990. ; 22:12, s. 839-69
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Tidskriftsartikel (refereegranskat)abstract
- Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.
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| 8. |
- Abdo, A. A., et al.
(författare)
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Multiwavelength Monitoring of the Enigmatic Narrow-Line Seyfert 1 PMN J0948+0022 in 2009 March-July
- 2009
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 707:1, s. 727-737
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Tidskriftsartikel (refereegranskat)abstract
- Following the recent discovery of γ rays from the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022 (z = 0.5846), we started a multiwavelength campaign from radio to γ rays, which was carried out between the end of 2009 March and the beginning of July. The source displayed activity at all the observed wavelengths: a general decreasing trend from optical to γ-ray frequencies was followed by an increase of radio emission after less than two months from the peak of the γ-ray emission. The largest flux change, about a factor of about 4, occurred in the X-ray band. The smallest was at ultraviolet and near-infrared frequencies, where the rate of the detected photons dropped by a factor 1.6-1.9. At optical wavelengths, where the sampling rate was the highest, it was possible to observe day scale variability, with flux variations up to a factor of about 3. The behavior of PMN J0948+0022 observed in this campaign and the calculated power carried out by its jet in the form of protons, electrons, radiation, and magnetic field are quite similar to that of blazars, specifically of flat-spectrum radio quasars. These results confirm the idea that radio-loud narrow-line Seyfert 1 galaxies host relativistic jets with power similar to that of average blazars.
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| 9. |
- Wilson, J. A., et al.
(författare)
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The optical links of the ATLAS SemiConductor tracker
- 2007
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 2, s. 1-28
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Tidskriftsartikel (refereegranskat)abstract
- Optical links are used for the readout of the 4088 silicon microstrip modules that make up the SemiConductor Tracker of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The optical link requirements are reviewed, with particular emphasis on the very demanding environment at the LHC. The on-detector components have to operate in high radiation levels for 10 years, with no maintenance, and there are very strict requirements on power consumption, material and space. A novel concept for the packaging of the on-detector optoelectronics has been developed to meet these requirements. The system architecture, including its redundancy features, is explained and the critical on-detector components are described. The results of the extensive Quality Assurance performed during all steps of the assembly are discussed.
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| 10. |
- Schoch, C. L., et al.
(författare)
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A class-wide phylogenetic assessment of Dothideomycetes
- 2009
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Ingår i: Studies in mycology. - : Westerdijk Fungal Biodiversity Institute. - 0166-0616 .- 1872-9797. ; 64, s. 1-15
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Forskningsöversikt (refereegranskat)abstract
- We present a comprehensive phylogeny derived from 5 genes, nucSSU, nucLSU rDNA, TEF1, RPB1 and RPB2, for 356 isolates and 41 families (six newly described in this volume) in Dothideomycetes. All currently accepted orders in the class are represented for the first time in addition to numerous previously unplaced lineages. Subclass Pleosporomycetidae is expanded to include the aquatic order Jahnulales. An ancestral reconstruction of basic nutritional modes supports numerous transitions from saprobic life histories to plant associated and lichenised modes and a transition from terrestrial to aquatic habitats are confirmed. Finally, a genomic comparison of 6 dothideomycete genomes with other fungi finds a high level of unique protein associated with the class, supporting its delineation as a separate taxon.
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| 11. |
- Burney, P., et al.
(författare)
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A case-control study of the relation between plasma selenium and asthma in European populations : a GAL2EN project
- 2008
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Ingår i: Allergy. European Journal of Allergy and Clinical Immunology. - : Wiley. - 0105-4538 .- 1398-9995. ; 63:7, s. 865-871
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There is evidence that selenium levels are relatively low in Europe and may be falling. Low levels of selenium or low activity of some of the enzymes dependent on selenium have been associated with asthma. METHODS: The GA(2)LEN network has organized a multicentre case-control study in Europe to assess the relation of plasma selenium to asthma. The network compared 569 cases in 14 European centres with a diagnosis of asthma and reporting asthma symptoms in the last 12 months with 576 controls from the same centres with no diagnosis of asthma and no asthmatic symptoms in the last 12 months. RESULTS: All cases and controls were selected from the same population defined by age and place of residence. Mean plasma selenium concentrations among the controls ranged from 116.3 microg/l in Palermo to 67.7 microg/l in Vienna and 56.1 microg/l among the children in Oslo. Random effects meta-analysis of the results from the centres showed no overall association between asthma and plasma selenium [odds ratio (OR)/10 microg/l increase in plasma selenium: 1.04; 95% confidence interval (CI): 0.89-1.21] though there was a significantly protective effect in Lodz (OR: 0.48; 95% CI: 0.29-0.78) and a marginally significant adverse effect in Amsterdam (OR: 1.68; 95% CI: 0.98-2.90) and Ghent (OR: 1.35; 95% CI: 1.03-1.77). CONCLUSION: This study does not support a role for selenium in protection against asthma, but effect modification and confounding cannot be ruled out.
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| 12. |
- Green, J. A., et al.
(författare)
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The 6-GHz multibeam maser survey-I. Techniques
- 2009
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 392:2, s. 783-794
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Tidskriftsartikel (refereegranskat)
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| 13. |
- Abdesselam, A., et al.
(författare)
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The detector control system of the ATLAS SemiConductor Tracker during macro-assembly and integration
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3, s. P02007-
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS SemiConductor Tracker (SCT) is one of the largest existing semiconductor detectors. It is situated between the Pixel detector and the Transition Radiation Tracker at one of the four interaction points of the Large Hadron Collider (LHC). During 2006-2007 the detector was lowered into the ATLAS cavern and installed in its final position. For the assembly, integration and commissioning phase, a complete Detector Control System (DCS) was developed to ensure the safe operation of the tracker. This included control of the individual powering of the silicon modules, a bi-phase cooling system and various types of sensors monitoring the SCT environment and the surrounding test enclosure. The DCS software architecture, performance and operational experience will be presented in the view of a validation of the DCS for the final SCT installation and operation phase.
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| 14. |
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| 15. |
- Leloudas, G., et al.
(författare)
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The normal Type Ia SN 2003hv out to very late phases
- 2009
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 505:1, s. 265-279
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Tidskriftsartikel (refereegranskat)abstract
- Aims: We study a thermonuclear supernova (SN), emphasizing very late phases. Methods: An extensive dataset for SN 2003hv that covers the flux evolution from maximum light to day +786 is presented. This includes 82 epochs of optical imaging, 24 epochs of near-infrared (NIR) imaging, and 10 epochs of optical spectroscopy. These data are combined with published nebular-phase IR spectra, and the observations are compared to model light curves and synthetic nebular spectra. Results: SN 2003hv is a normal Type Ia supernova (SN Ia) with photometric and spectroscopic properties consistent with its rarely observed B-band decline-rate parameter, Δ m15(B) = 1.61 ± 0.02. The blueshift of the most isolated [Fe ii] lines in the nebular-phase optical spectrum appears consistent with those observed in the IR at similar epochs. At late times there is a prevalent color evolution from the optical toward the NIR bands. We present the latest-ever detection of a SN Ia in the NIR in Hubble Space Telescope images. The study of the ultraviolet/optical/infrared (UVOIR) light curve reveals that a substantial fraction of the flux is “missing” at late times. Between 300 and 700 days past maximum brightness, the UVOIR light curve declines linearly following the decay of radioactive 56Co, assuming full and instantaneous positron trapping. At 700 days we detect a possible slowdown of the decline in optical-bands, mainly in the V-band. Conclusions: The data are incompatible with a dramatic infrared catastrophe (IRC). However, the idea that an IRC occurred in the densest regions before 350 days can explain the missing flux from the UVOIR wavelengths and the flat-topped profiles in the NIR. We argue that such a scenario is possible if the ejecta are clumpy. The observations suggest that positrons are most likely trapped in the ejecta. Based on observations collected at the European Southern Observatory, Paranal, Chile (ESO Programmes 073.D-0294(AB), 074.D-0259(BC) and 075.D-0116(AB)), Cerro Tololo Inter-American Observatory, Lick Observatory, Las Campanas Observatory, Siding Spring Observatory, and the Hubble Space Telescope. Tables 3, 4, and Appendix A are only available in electronic form at http://www.aanda.org
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| 16. |
- Shein, K.A., et al.
(författare)
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State of the Climate in 2005
- 2006
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Ingår i: Bulletin of American Meteorological Society. ; 87:6, s. 1-102
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Tidskriftsartikel (refereegranskat)
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| 17. |
- Graves, Genevieve J. M., et al.
(författare)
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Limits from the Hubble Space Telescope on a Point Source in SN 1987A
- 2005
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 629, s. 944-959
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Tidskriftsartikel (refereegranskat)abstract
- We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) in 1999 September and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. Our spectral observations cover ultraviolet (UV) and optical wavelengths from 1140 to 10266 Å, and our imaging observations cover UV and optical wavelengths from 2900 to 9650 Å. No point source is observed in the remnant. We obtain a limiting flux of Fopt<=1.6×10-14 ergs s-1 cm-2 in the wavelength range 2900-9650 Å for any continuum emitter at the center of the supernova remnant (SNR). This corresponds to an intrinsic luminosity of Lopt<=5×1033 ergs s-1. It is likely that the SNR contains opaque dust that absorbs UV and optical emission, resulting in an attenuation of ~35% due to dust absorption in the SNR. Correcting for this level of dust absorption would increase our upper limit on the luminosity of a continuum source by a factor of 1.54. Taking into account dust absorption in the remnant, we find a limit of Lopt<=8×1033 ergs s-1. We compare this upper bound with empirical evidence from point sources in other supernova remnants and with theoretical models for possible compact sources. We show that any survivor of a possible binary system must be no more luminous than an F6 main-sequence star. Bright young pulsars such as Kes 75 or the Crab pulsar are excluded by optical and X-ray limits on SN 1987A. Other nonplerionic X-ray point sources have luminosities similar to the limits on a point source in SN 1987A; RCW 103 and Cas A are slightly brighter than the limits on SN 1987A, while Pup A is slightly fainter. Of the young pulsars known to be associated with SNRs, those with ages <=5000 yr are all too bright in X-rays to be compatible with the limits on SN 1987A. Examining theoretical models for accretion onto a compact object, we find that spherical accretion onto a neutron star is firmly ruled out and that spherical accretion onto a black hole is possible only if there is a larger amount of dust absorption in the remnant than predicted. In the case of thin-disk accretion, our flux limit requires a small disk, no larger than 1010 cm, with an accretion rate no more than 0.3 times the Eddington accretion rate. Possible ways to hide a surviving compact object include the removal of all surrounding material at early times by a photon-driven wind, a small accretion disk, or very high levels of dust absorption in the remnant. It will not be easy to improve substantially on our optical-UV limit for a point source in SN 1987A, although we can hope that a better understanding of the thermal infrared emission will provide a more complete picture of the possible energy sources at the center of SN 1987A.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Gangopadhyay, S., et al.
(författare)
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C-60 submonolayers on the Si(111)-(7 x 7) surface: Does a mixture of physisorbed and chemisorbed states exist?
- 2009
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Ingår i: Surface Science. - : Elsevier BV. - 0039-6028. ; 603:18, s. 2896-2901
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Tidskriftsartikel (refereegranskat)abstract
- We have carried out a combined X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy(UPS), and scanning tunnelling microscopy (STM) study of the C-60-Si(1 1 1) interaction where the XPS/UPS spectrometer and STM are integrated on a single UHV system. This enables a direct comparison of the XPS/UPS spectra with the STM data and eliminates any uncertainty in C-60 coverage measurements. X-ray standing wave measurements and density functional theory calculations have been used to support and interpret the results of the XPS/UPS/STM experiments. Our data conclusively rule out models of C-60 adsorption which involve a mixture of physisorbed and chemisorbed molecules [K. Sakamoto, et al., Phys. Rev. B 60 (1999) 2579]. Instead, we find that all molecules, up to 1 monolayer coverage, bond to the surface via Si-C bonds which are predominantly of covalent character. (C) 2009 Elsevier B.V. All rights reserved.
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| 22. |
- Kirkland, Thomas A., et al.
(författare)
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Synthesis of glutamic acid analogs as potent inhibitors of leukotriene A(4) hydrolase
- 2008
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Ingår i: Bioorganic & Medicinal Chemistry. - : Elsevier BV. - 0968-0896 .- 1464-3391. ; 16:9, s. 4963-4983
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Tidskriftsartikel (refereegranskat)abstract
- Leukotriene B-4 (LTB4) is a potent pro-inflammatory mediator that has been implicated in the pathogenesis of multiple diseases, including psoriasis, inflammatory bowel disease, multiple sclerosis and asthma. As a method to decrease the level of LTB4 and possibly identify novel treatments, inhibitors of the LTB4 biosynthetic enzyme, leukotriene A(4) hydrolase (LTA(4)-h), have been explored. Here we describe the discovery of a potent inhibitor of LTA(4)-h, arylamide of glutamic acid 4f, starting from the corresponding glycinamide 2. Analogs of 4f are then described, focusing on compounds that are both active and stable in whole blood. This effort culminated in the identification of amino alcohol 12a and amino ester 6b which meet these criteria.
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| 23. |
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| 24. |
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| 25. |
- Zhao, Ming, et al.
(författare)
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Strain-symmetrized Si/SiGe multi-quantum well structures grown by molecular beam epitaxy for intersubband engineering
- 2006
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Ingår i: Journal of luminescence. - : Elsevier BV. - 0022-2313. ; 121:2, s. 403-408
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Tidskriftsartikel (refereegranskat)abstract
- Three strain-symmetrized Si/SiGe multi-quantum well structures, designed for probing the carrier lifetime of intrawell intersubband transitions between heavy hole 1 (HH1) and light hole 1 (LH1) states with transition energies below the optical phonon energy, were grown by molecular beam epitaxy at low temperature on fully relaxed SiGe virtual substrates. The grown structures were characterized by using various experimental techniques, showing a high crystalline quality and very precise growth control. The lifetime of the LH1 excited state was determined directly with pump-probe spectroscopy. The measurements indicated an increase of the lifetime by a factor of 2 due to the increasingly unconfined LH1 state, which agreed very well with the design. It also showed a very long lifetime of several hundred picoseconds for the holes excited out of the well to transit back to the well through a diagonal process.
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| 26. |
- Allen, S. L., et al.
(författare)
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C-13 transport studies in L-mode divertor plasmas on DIII-D
- 2005
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Ingår i: Journal of Nuclear Materials. - : Elsevier BV. - 0022-3115 .- 1873-4820. ; 337-39:03-jan, s. 30-34
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Tidskriftsartikel (refereegranskat)abstract
- (CH4)-C-13 was injected with a toroidally-symmetric gas system into 22 identical lower-single-null L-mode discharges on DIII-D. The injection level was adjusted so that it did not significantly perturb the core or divertor plasmas, with a duration of similar to 3 s on each shot, for a total of similar to 300 T L of injected particles. The plasma shape remained very constant; the divertor strike points were controlled to similar to 1 cm at the divertor plate. At the beginning of the subsequent machine vent, 29 carbon tiles were removed for nuclear reaction analysis of C-13 content to determine regions of carbon deposition. It was found that only the tiles inboard of the inner strike point had appreciable 1 3 C above background. Visible spectroscopy measurements of the carbon injection and comparisons with modeling are consistent with carbon transport by means of scrape-off layer flow.
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Clocchiatti, Alejandro, et al.
(författare)
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Late-time HST photometry of SN1994I : Hints of positron annihilation energy deposition
- 2008
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Ingår i: Publications of the Astronomical Society of the Pacific. - : IOP Publishing. - 0004-6280 .- 1538-3873. ; 120:865, s. 290-300
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Tidskriftsartikel (refereegranskat)abstract
- We present multicolor Hubble Space Telescope ( HST) WFPC2 broadband observations of the Type Ic SN 1994I obtained similar to 280 d after maximum light. We measure the brightness of the SN and, relying on the detailed spectroscopic database of SN 1994I, we transform the ground-based photometry obtained at early times to the HST photometric system, deriving light curves for the WFPC2 F439W, F555W, F675W, and F814W passbands that extend from 7 days before to 280 days after maximum. We use the multicolor photometry to build a quasi-bolometric light curve of SN 1994I, and compare it with similarly constructed light curves of other supernovae. In doing so, we propose and test a scaling in energy and time that allows for a more meaningful comparison of the exponential tails of different events. Through comparison with models, we find that the late-time light curve of SN 1994I is consistent with that of spherically symmetric ejecta in homologous expansion, for which the ability to trap the gamma-rays produced by the radioactive decay of Co-56 diminishes roughly as the inverse of time squared. We also find that by the time of the HST photometry, the light curve was significantly energized by the annihilation of positrons.
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| 31. |
- Cocks, K., et al.
(författare)
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An internadional field study of the reliability and validity of a disease-specfic questionnanire module (the QLQ-MY20) in assessing the quality of life of patients with multiple myeloma
- 2007
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Ingår i: European Journal of Cancer. - : Elsevier BV. - 1879-0852 .- 0959-8049. ; 43:11, s. 1670-1678
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To test the reliability, validity and sensitivity of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-MY24 questionnaire, designed to assess the quality of life of myeloma patients with the QLQ-C30. Methods: The study was carried out through the EORTC Quality of Life Group using clinical trials in seven countries. All trials used the QLQ-C30 and QLQ-MY24 at baseline and a follow-up timepoint. Results: Two hundred and forty patients participated. The questionnaires were acceptable to patients. The hypothesised scale structure (disease symptoms, side-effects, body image and future perspective) was confirmed by multi-trait scaling, internal consistency and correlation analysis. Most scales demonstrated sensitivity to change and discriminated between clinically different patients. The social support scale (4 items) was removed due to observed ceiling effects. Conclusion: The final questionnaire contains 20 items, QLQ-MY20, and is a reliable and valid instrument recommended for use with the QLQ-C30 in myeloma patients. (c) 2007 Elsevier Ltd. All rights reserved.
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| 32. |
- Copland, DA, et al.
(författare)
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Monoclonal antibody-mediated CD200 receptor signaling suppresses macrophage activation and tissue damage in experimental autoimmune uveoretinitis
- 2007
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Ingår i: American Journal of Pathology. - : Elsevier BV. - 0002-9440 .- 1525-2191. ; 171:2, s. 580-588
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Tidskriftsartikel (refereegranskat)abstract
- Macrophage responses are regulated by multiple secreted factors as well as by cell surface receptors, including the inhibitory signals resulting from ligation of myeloid CD200 receptors (CD200R) by the widely distributed CD200. In the absence of CD200, animals display increased susceptibility to autoimmunity and earlier onset aggressive autoimmune disease. In these current experiments, an agonist monoclonal rat anti-mouse CD200R (DX109) antibody delivered a negative signal to bone marrow-derived macrophages, which suppressed interferon (IFN)-mediated nitric oxide (NO) and interleukin-6 production. Experimental autoimmune uveoretinitis (EAU) was used as a model of organ-specific autoimmunity in the eye, a tissue with extensive neuronal and endothelial CD200 expression. In mice lacking CD200 (CD200-/-), increased numbers of retina-infiltrating macrophages displaying heightened NO responses were observed during EAU. In addition, we aimed to suppress disease by maintaining tonic suppression of macrophage activation via CD200R. Systemically administered DX109 monoclonal antibody suppressed EAU despite maintained T-cell proliferation and IFN production. Furthermore, locally administered DX109 monoclonal antibody resulted in an earlier resolution of disease. These experiments demonstrate that promoting CD200R-mediated signaling can successfully prevent full expression of IFN-mediated macrophage activation and protect against tissue damage during autoimmune responses.
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| 33. |
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| 34. |
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| 35. |
- Hoskin, Peter J, et al.
(författare)
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Acute and late morbidity in the treatment of advanced bladder carcinoma with accelerated radiotherapy, carbogen, and nicotinamide
- 2005
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Ingår i: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 103:11, s. 2287-2297
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Accelerated radiotherapy combined with carbogen and nicotinamide (ARCON) to overcome tumor hypoxia and cell proliferation achieved high tumor control and survival in Phase II studies of patients with advanced head and neck and bladder carcinomas. Thus, morbidity and treatment outcomes from the latter study were analyzed to evaluate the therapeutic potential of ARCON. METHODS: Acute and late morbidity was assessed in 105 patients with high-grade superficial or muscle-invasive bladder carcinoma who were given accelerated radiotherapy (50-55 grays in 4 weeks) with carbogen alone or with ARCON. Urinary dysfunction was scored based on daytime frequency, nocturia, incontinence, dysuria, hematuria, and urgency. Bowel morbidity was based on stool frequency and consistency, rectal discharge, blood loss, and medication. Endpoints for treatment outcome were overall survival, disease-free survival, and locoregional control. RESULTS: Nearly all patients experienced reduced ability to retain urine beyond 2 hours, although 20-30% had almost normal function at night. Incidence of acute moderate or worse dysuria was 41% with ARCON and 56% with carbogen; 96% and 76% of patients, respectively, had bowel frequencies > or = 3 times per day. By 10-12 weeks from the start of radiotherapy, acute reactions returned to baseline levels. At 3 years, the daytime frequency < or = 2 times per hour was approximately 75% in both arms. Incidence of severe hematuria (< or = 25%) and urinary urgency (< or = 16%) was much lower. No more than 6% of patients had severe bowel morbidity. With most assays, the differences between schedules were not significant either for acute or late morbidity. Local tumor control and survival rates at 3 years were 53% and 43%, respectively, for ARCON, similar to the rates for carbogen alone. CONCLUSIONS: Historical comparisons suggested no overt increase in normal tissue radiosensitivity when adding carbogen and nicotinamide. Although, for some endpoints, the incidence of late sequelae was higher than expected, overall morbidity was no worse than reported by others. The data indicated that ARCON could achieve a therapeutic gain in patients with advanced bladder carcinoma. A Phase III, randomized, multicenter trial is underway currently in the United Kingdom to evaluate these findings.
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| 36. |
- Ivanov, Alexander, et al.
(författare)
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Boronate-containing polymer brushes: Characterization, interaction with saccharides and mammalian cancer cells.
- 2009
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Ingår i: Journal of Biomedical Materials Research. Part A. - : Wiley. - 1552-4965 .- 1549-3296. ; 88:1, s. 213-225
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Tidskriftsartikel (refereegranskat)abstract
- Boronate-containing polymer brushes were synthesized by free radical copolymerization of N,N-dimethylacrylamide (DMAA) and N-acryloyl-m-phenylboronic acid (NAAPBA) (9:1) on the surface of 3-mercaptopropyl-silylated glass plates and capillaries. The brushes were characterized with time-of-flight secondary ion mass-spectrometry (ToF SIMS), atomic force microscopy and contact angle measurements. Fructose caused a well-expressed drop spreading on the surface of copolymer-grafted glass, due to the strong interaction with the boronate groups. Sedimentation of murine hybridoma cells M2139 or human myeloid leukemia cells KG1 onto the DMAA-NAAPBA copolymer-grafted glass plates from 10 mM phosphate buffer solution (pH 8.0) resulted in the cell adhesion. The adhered M2139 and KG1 cells could be quantitatively detached from the grafted plates with 0.1M fructose, which competed with cell surface carbohydrates for binding to the boronates. Evaluation of the binding strength between M2139 cells and the copolymer brush was performed by exposure of the adhered cells to a shear stress. Detachment of a fraction of 18% of the adhered M2139 cells was obtained at a shear force of 1400-2800 pN/cell generated by the running phosphate buffer (pH 8.0), whereas the remaining adhered cells (70%) could be detached with 0.1M fructose dissolved in the same buffer. Possible applications of the boronate-containing polymer brushes to affinity cell separation can be based upon the facile recovery of the attached cells. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008.
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| 37. |
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| 38. |
- Kuimova, M. K., et al.
(författare)
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Determination of the triplet state energies of a series of conjugated porphyrin oligomers
- 2007
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Ingår i: Photochemical and Photobiological Sciences. - : Springer Science and Business Media LLC. - 1474-9092 .- 1474-905X. ; 6:6, s. 675-682
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Tidskriftsartikel (refereegranskat)abstract
- We report a systematic study of the photophysical parameters relevant to photodynamic therapy (PDT) by a new type of sensitizers, conjugated porphyrin oligomers. Due to the strong nonlinear properties of oligomers containing 2, 4 and 8 porphyrin units, these molecules are attractive candidates for PDT via multiphoton excitation. The triplet state energy levels for all molecules have been determined by the triplet quenching method, phosphorescence measurements and DFT calculations. We find that the triplet energies of all the oligomers are sufficient to generate singlet oxygen, > 94 kJ mol(-1). However, low singlet oxygen quantum yields are observed for the tetramer and the octamer, as compared to the conjugated dimer and monomeric porphyrin, reflecting the decrease in triplet yield. Thus the conjugated porphyrin dimer is the most promising core structure for PDT applications via multiphoton excitation.
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| 39. |
- Lee, S. S., et al.
(författare)
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Sensitivity of aerosol and cloud effects on radiation to cloud types: comparison between deep convective clouds and warm stratiform clouds over one-day period
- 2009
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Ingår i: Atmospheric Chemistry and Physics. - 1680-7324. ; 9:7, s. 2555-2575
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Tidskriftsartikel (refereegranskat)abstract
- Cloud and aerosol effects on radiation in two contrasting cloud types, a deep mesoscale convective system (MCS) and warm stratocumulus clouds, are simulated and compared. At the top of the atmosphere, 45-81% of shortwave cloud forcing (SCF) is offset by longwave cloud forcing (LCF) in the MCS, whereas warm stratiform clouds show the offset of less than similar to 20%. 28% of increased negative SCF is offset by increased LCF with increasing aerosols in the MCS at the top of the atmosphere. However, the stratiform clouds show the offset of just around 2-5%. Ice clouds as well as liquid clouds play an important role in the larger offset in the MCS. Lower cloud-top height and cloud depth, characterizing cloud types, lead to the smaller offset of SCF by LCF and the offset of increased negative SCF by increased LCF at high aerosol in stratocumulus clouds than in the MCS. Supplementary simulations show that this dependence of modulation of LCF on cloud depth and cloud-top height is also simulated among different types of convective clouds.
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| 40. |
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| 41. |
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| 42. |
- Morgan-Richards, Mary, et al.
(författare)
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Bird evolution: testing the Metaves clade with six new mitochondrial genomes
- 2008
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Ingår i: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 8:20
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Tidskriftsartikel (refereegranskat)abstract
- Background: Evolutionary biologists are often misled by convergence of morphology and this has been common in the study of bird evolution. However, the use of molecular data sets have their own problems and phylogenies based on short DNA sequences have the potential to mislead us too. The relationships among clades and timing of the evolution of modern birds (Neoaves) has not yet been well resolved. Evidence of convergence of morphology remain controversial. With six new bird mitochondrial genomes (hummingbird, swift, kagu, rail, flamingo and grebe) we test the proposed Metaves/Coronaves division within Neoaves and the parallel radiations in this primary avian clade. Results: Our mitochondrial trees did not return the Metaves clade that had been proposed based on one nuclear intron sequence. We suggest that the high number of indels within the seventh intron of the beta-fibrinogen gene at this phylogenetic level, which left a dataset with not a single site across the alignment shared by all taxa, resulted in artifacts during analysis. With respect to the overall avian tree, we find the flamingo and grebe are sister taxa and basal to the shorebirds (Charadriiformes). Using a novel site-stripping technique for noise-reduction we found this relationship to be stable. The hummingbird/swift clade is outside the large and very diverse group of raptors, shore and sea birds. Unexpectedly the kagu is not closely related to the rail in our analysis, but because neither the kagu nor the rail have close affinity to any taxa within this dataset of 41 birds, their placement is not yet resolved. Conclusion: Our phylogenetic hypothesis based on 41 avian mitochondrial genomes ( 13,229 bp) rejects monophyly of seven Metaves species and we therefore conclude that the members of Metaves do not share a common evolutionary history within the Neoaves.
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| 43. |
- Morran, Levi T, et al.
(författare)
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Sexual partners for the stressed : facultative outcrossing in the self-fertilizing nematode Caenorhabditis elegans.
- 2009
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Ingår i: Evolution. - : Wiley. - 0014-3820 .- 1558-5646. ; 63:6
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Tidskriftsartikel (refereegranskat)abstract
- Sexual reproduction shuffles genetic variation, potentially enhancing the evolutionary response to environmental change. Many asexual organisms respond to stress by generating facultative sexual reproduction, presumably as a means of escaping the trap of low genetic diversity. Self-fertilizing organisms are subject to similar genetic limitations: the consistent loss of genetic diversity within lineages restricts the production of variation through recombination. Selfing organisms may therefore benefit from a similar shift in mating strategy during periods of stress. We determined the effects of environmental stress via starvation and passage through the stress-resistant dauer stage on mating system dynamics of Caenorhabditis elegans, which reproduces predominantly through self-fertilization but is capable of outcrossing in the presence of males. Starvation elevated male frequencies in a strain-specific manner through differential male survival during dauer exposure and increased outcrossing rates after dauer exposure. In the most responsive strain, the mating system changed from predominantly selfing to almost exclusively outcrossing. Like facultative sex in asexual organisms, facultative outcrossing in C. elegans may periodically facilitate adaptation under stress. Such a shift in reproductive strategy should have a major impact on evolutionary change within these populations and may be a previously unrecognized feature of other highly selfing organisms.
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| 44. |
- Muheim, Rachel, et al.
(författare)
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Calibration of magnetic and celestial compass cues in migratory birds - a review of cue-conflict experiments
- 2006
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 1477-9145 .- 0022-0949. ; 209:1, s. 2-17
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Forskningsöversikt (övrigt vetenskapligt/konstnärligt)abstract
- Migratory birds use multiple sources of compass information for orientation, including the geomagnetic field, the sun, skylight polarization patterns and star patterns. In this paper we review the results of cue-conflict experiments designed to determine the relative importance of the different compass mechanisms, and how directional information from these compass mechanisms is integrated. We focus on cue-conflict experiments in which the magnetic field was shifted in alignment relative to natural celestial cues. Consistent with the conclusions of earlier authors, our analyses suggest that during the premigratory season, celestial information is given the greatest salience and used to recalibrate the magnetic compass by both juvenile and adult birds. Sunset polarized light patterns from the region of the sky near the horizon appear to provide the calibration reference for the magnetic compass. In contrast, during migration, a majority of experiments suggest that birds rely on the magnetic field as the primary source of compass information and use it to calibrate celestial compass cues, i.e. the relative saliency of magnetic and celestial cues is reversed. An alternative possibility, however, is suggested by several experiments in which birds exposed to a cue conflict during migration appear to have recalibrated the magnetic compass, i.e. their response is similar to that of birds exposed to cue conflicts during the premigratory season. The general pattern to emerge from these analyses is that birds exposed to the cue conflict with a view of the entire sunset sky tended to recalibrate the magnetic compass, regardless of whether the cue conflict occurred during the premigratory or migratory period. In contrast, birds exposed to the cue conflict in orientation funnels and registration cages that restricted their view of the region of sky near the horizon (as was generally the case in experiments carried out during the migratory season) did not recalibrate the magnetic compass but, instead, used the magnetic compass to calibrate the other celestial compass systems. If access to critical celestial cues, rather than the timing of exposure to the cue conflict (i.e. premigratory vs migratory), determines whether recalibration of the magnetic compass occurs, this suggests that under natural conditions there may be a single calibration reference for all of the compass systems of migratory birds that is derived from sunset (and possibly also sunrise) polarized light cues from the region of sky near the horizon. In cue-conflict experiments carried out during the migratory season, there was also an interesting asymmetry in the birds' response to magnetic fields shifted clockwise and counterclockwise relative to celestial cues. We discuss two possible explanations for these differences: (1) lateral asymmetry in the role of the right and left eye in mediating light-dependent magnetic compass orientation and (2) interference from the spectral and intensity distribution of skylight at sunset with the response of the light-dependent magnetic compass.
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| 45. |
- Muheim, Rachel, et al.
(författare)
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Polarized light cues underlie compass calibration in migratory songbirds
- 2006
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 313:5788, s. 837-839
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunrise and sunset. We suggest that skylight polarization patterns are used to derive an absolute (i.e., geographic) directional system that provides the primary calibration reference for all of the compasses of migratory songbirds.
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| 46. |
- Penning, W. Ellis, et al.
(författare)
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Using aquatic macrophyte community indices to define the ecological status of European lakes
- 2008
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Ingår i: Aquatic Ecology. - : Springer Science and Business Media LLC. - 1386-2588 .- 1573-5125. ; 42:2, s. 253-264
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Tidskriftsartikel (refereegranskat)abstract
- Defining the overall ecological status of lakes according to the Water Framework Directive (WFD) is to be partially based on the species composition of the aquatic macrophyte community. We tested three assessment methods to define the ecological status of the macrophyte community in response to a eutrophication pressure as reflected by total phosphorus concentrations in lake water. An absolute species richness, a trophic index (TI) and a lake trophic ranking (LTR) method were tested at Europe-wide, regional and national scales as well as by alkalinity category, using data from 1,147 lakes from 12 European states. Total phosphorus data were used to represent the trophic status of individual samples and were plotted against the calculated TI and LTR values. Additionally, the LTR method was tested in some individual lakes with a relatively long time series of monitoring data. The TI correlated well with total P in the Northern European lake types, whereas the relationship in the Central European lake types was less clear. The relationship between total P and light extinction is often very good in the Northern European lake types compared to the Central European lake types. This can be one of the reasons for a better agreement between the indices and eutrophication pressure in the Northern European lake types. The response of individual lakes to changes in the abiotic environment was sometimes represented incorrectly by the indices used, which is a cause of concern for the use of single indices in status assessments in practice.
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| 47. |
- Phillips, C. L., et al.
(författare)
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The effect of short-term withdrawal from continuous positive airway pressure therapy on sympathetic activity and markers of vascular inflammation in subjects with obstructive sleep apnoea
- 2007
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Ingår i: J Sleep Res. - 0962-1105. ; 16:2, s. 217-25
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Tidskriftsartikel (refereegranskat)abstract
- Obstructive sleep apnoea (OSA) is commonly associated with cardiovascular disease and sympathetic activation. However, it is unclear whether this association is independent of obesity and to what extent treatment with nasal continuous positive airway pressure (CPAP) alleviates the vascular inflammation that underpins cardiovascular disease. We therefore evaluated whether short-term withdrawal from CPAP therapy in subjects with moderate-severe OSA would result in increased levels of sympathetic activity and circulating inflammatory cytokines independent of weight. Vascular inflammatory markers (hsCRP, hsIL-6 and hsTNF-alpha) were assessed in 20 subjects after one and seven nights of withdrawal from CPAP together with the hypoxia-responsive angiogenic marker VEGF and urinary catecholamines. Compared with baseline on CPAP, withdrawal from therapy resulted in an immediate return of OSA with an increase in RDI to 26.7 +/- 5.2 and 39.0 +/- 5.9 events per hour after one and seven nights without CPAP, respectively (both P < 0.0001). This was accompanied by a concomitant rise in daytime urinary noradrenaline (P < 0.0001) after seven nights CPAP withdrawal that was positively associated with the severity of hypoxaemia. In contrast, withdrawal from CPAP therapy was not accompanied by any change in measured cytokines or VEGF (all P > 0.1). In conclusion, 1 week of CPAP withdrawal was associated with a return of OSA and a marked increase in sympathetic activity without a concomitant elevation of vascular inflammatory markers.
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| 48. |
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| 49. |
- Probert, Christopher S J, et al.
(författare)
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The effect of weaning on the clonality of alpha beta T-cell receptor T cells in the intestine of GF and SPF mice.
- 2007
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Ingår i: Developmental and comparative immunology. - : Elsevier BV. - 0145-305X. ; 31:6, s. 606-17
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Tidskriftsartikel (refereegranskat)abstract
- In humans, intestinal antigen exposure during neonatal life influences the T-cell receptor (TCR) repertoire. To define the relative effects of bacteria and food antigens in early life, we examined TCR diversity in the intestine of SPF and GF mice. TCR repertoire was assessed at a single time point pre-, peri- and post-weaning in the small and large intestine of SPF and GF mice using spectratyping and/or TCR-beta-chain sequencing. There was good concordance of data obtained by the two techniques. In SPF mice, the repertoire was polyclonal shortly after birth in the small and large intestine. After weaning, there was a significant change towards an oligoclonal repertoire in the small intestine. There was some evidence that specific clones were shared between the small and large intestine. In contrast, in GF mice, the repertoire was oligoclonal after birth, and remained restricted. These data show: firstly, that under SPF conditions, the intestine is seeded with a diverse T-cell population that becomes oligoclonal around the time of weaning; secondly, that GF mice were oligoclonal at each time point.
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| 50. |
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