SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Wark Michael) "

Search: WFRF:(Wark Michael)

  • Result 1-9 of 9
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • McElvaney, Noel G., et al. (author)
  • Long-term efficacy and safety of α1 proteinase inhibitor treatment for emphysema caused by severe α1 antitrypsin deficiency : an open-label extension trial (RAPID-OLE)
  • 2017
  • In: The Lancet Respiratory Medicine. - 2213-2600. ; 5:1, s. 51-60
  • Journal article (peer-reviewed)abstract
    • Background Purified α1 proteinase inhibitor (A1PI) slowed emphysema progression in patients with severe α1 antitrypsin deficiency in a randomised controlled trial (RAPID-RCT), which was followed by an open-label extension trial (RAPID-OLE). The aim was to investigate the prolonged treatment effect of A1PI on the progression of emphysema as assessed by the loss of lung density in relation to RAPID-RCT. Methods Patients who had received either A1PI treatment (Zemaira or Respreeza; early-start group) or placebo (delayed-start group) in the RAPID-RCT trial were included in this 2-year open-label extension trial (RAPID-OLE). Patients from 22 hospitals in 11 countries outside of the USA received 60 mg/kg per week A1PI. The primary endpoint was annual rate of adjusted 15th percentile lung density loss measured using CT in the intention-to-treat population with a mixed-effects regression model. This trial is registered with ClinicalTrials.gov, number NCT00670007. Findings Between March 1, 2006, and Oct 13, 2010, 140 patients from RAPID-RCT entered RAPID-OLE: 76 from the early-start group and 64 from the delayed-start group. Between day 1 and month 24 (RAPID-RCT), the rate of lung density loss in RAPID-OLE patients was lower in the early-start group (−1·51 g/L per year [SE 0·25] at total lung capacity [TLC]; −1·55 g/L per year [0·24] at TLC plus functional residual capacity [FRC]; and −1·60 g/L per year [0·26] at FRC) than in the delayed-start group (−2·26 g/L per year [0·27] at TLC; −2·16 g/L per year [0·26] at TLC plus FRC, and −2·05 g/L per year [0·28] at FRC). Between months 24 and 48, the rate of lung density loss was reduced in delayed-start patients (from −2·26 g/L per year to −1·26 g/L per year), but no significant difference was seen in the rate in early-start patients during this time period (−1·51 g/L per year to −1·63 g/L per year), thus in early-start patients the efficacy was sustained to month 48. Interpretation RAPID-OLE supports the continued efficacy of A1PI in slowing disease progression during 4 years of treatment. Lost lung density was never recovered, highlighting the importance of early intervention with A1PI treatment. Funding CSL Behring.
  •  
2.
  • Sondhauss, Peter, et al. (author)
  • Picosecond x-ray studies of coherent folded acoustic phonons in a periodic semiconductor heterostructure
  • 2006
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 1996-756X .- 0277-786X. ; 6118, s. 1180-1180
  • Conference paper (peer-reviewed)abstract
    • Zone folded coherent acoustic phonons were generated in a multilayered GaSb/InAs epitaxial heterostructure via rapid heating by femtosecond laser pulses. These phonons were probed by means of ultrafast x-ray diffraction. Phonons both from the fundamental acoustic branch and the first back-folded branch were detected. This represents the first clear evidence for phonon branch folding based directly on the atomic motion to which x-ray diffraction is sensitive. From a comparison of the measured phonon-modulated x-ray reflectivity with simulations, evidence was found for a reduction of the laser penetration depth. This reduction can be explained by the self-modulation of the absorption index due to photogenerated free carriers.
  •  
3.
  • Alammar, Tarek, et al. (author)
  • Microwave-Assisted Synthesis of Perovskite SrSnO3 Nanocrystals in Ionic Liquids for Photocatalytic Applications
  • 2017
  • In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 56:12, s. 6920-6932
  • Journal article (peer-reviewed)abstract
    • Nanosized SrSnO3 photocatalysts have been successfully synthesized by microwave synthesis in various ionic liquids (ILs) followed by a heat treatment process to optimize the materials' crystallinity. The influence of the ILs with various cations such as 1-butyl-3-methylimidazolium ([C(4)mim](+)), 6-bis(3-methylimidazolium-1-yl)hexane ([C-6(mim)(2)](2+)), butylpyridinium ([C4Py](+)), and tetradecyltrihexylphosphonium ([P-66614](+)) and bis(trifluoromethanesulfonyl)amide ([Tf2N](-)) as the anion on the structure, crystallization, and morphology of the products was investigated. The samples were characterized by X-ray diffraction (XRD), thermogravimetry (TG), scanning electron microscopy (SEM), surface area analysis by gas adsorption, X-ray photoelectron spectroscopy (XPS), diffuse reflectance UV vis spectroscopy, and Raman and IR spectroscopy. According to structure characterization by XRD and Raman spectroscopy all samples wcrystallized phase-pure in the orthorhombic GdFeO3 perovskite structure type. SEM reveals that, on the basis of the IL, th(e) obtained SrSnO3 nanoparticles exhibit different morphologies and sizes. Rod-shaped particles are formed in [C(4)minn][Tf2N], [C-6(mim)(2)][Tf2N](2), and p [P-66614][Tf2N]. However, the particle dimensions and size distribution vary depending on the IL and range from quite thin and long needlelike partinles with a narrow size distribution obtained in [P-66614] [TfA to relatively larger particles with a broader size distribution obtained in [C-6(mim)(2)][Tf2N](2). In contrast, in [C4Py][Tf2N] nanospheres with a diameter of about 50 nm form. For these particles the highest photocatalytic activity was observed. Our investigations indicate that the improved photocatalytic activity of this material results from the synergistic effect of the relatively large surface area associated with nanosize and an appropriate energy band structure.
  •  
4.
  • Alammar, Tarek, et al. (author)
  • The Power of Ionic Liquids : Crystal Facet Engineering of SrTiO3 Nanoparticles for Tailored Photocatalytic Applications
  • 2021
  • In: Advanced Sustainable Systems. - : Wiley. - 2366-7486. ; 5:2
  • Journal article (peer-reviewed)abstract
    • Sonochemical synthesis of nano-sized SrTiO3 carried out at close to room temperature, in ionic liquids (ILs) allows the tuning of particle size and particle morphology, that is, tracht and habitus, as well as particle aggregation via the choice of the ionic liquids (ILs) as the reaction medium. The nanoparticles demonstrate high performance for photocatalytic water splitting and photodecomposition of organic material. To this end bis(trifluoromethanesulfonyl)amide ([Tf2N](-))-based ILs with cations of different properties with respect to specific interactions with the target material are investigated. Isolated, 15 +/- 1 nm sized nano-spheres of SrTiO3 are observed to form in [C(3)mimOH][Tf2N] ([C(3)mimOH](+) = 1-(3-hydroxypropyl)-3-methylimidazolium). Aggregation of small sized nanoparticles are observed to around 250 +/- 100 nm large cube-like formations in [C(4)mim][Tf2N] ([C(4)mim](+) = 1-butyl-3-methylimidazolium), raspberry-like in [C4Py][Tf2N] ([C4Py](+) butylpyridinium), and ball-like in [P-66614][Tf2N] ([P-66614](+) tetradecyltrihexyl phosphonium). Importantly, the different materials show different performance as photocatalysts. SrTiO3 prepared in [C(4)mim][Tf2N] shows the highest photocatalytic activity for H-2 evolution (1115.4 mu mol h(-1)) when using 0.025 wt% Rh as the co-catalyst, whereas the material prepared in [C(3)mimOH][Tf2N] shows the highest activity for the photocatalytic degradation of methylene blue (88%) under UV irradiation. The different photocatalytic activities can be correlated with the different crystal surface facets expressed in the respective nanosized SrTiO3 material, {110} for material obtained from [C(4)mim][Tf2N], and {100} for material from [C(3)mimOH][Tf2N]. First-principles density functional theory (DFT) calculations are used to support the experimental findings.
  •  
5.
  •  
6.
  • Larsson, Jörgen, et al. (author)
  • Time-resolved X-ray diffraction study of the ferroelectric phase-transition in DKDP
  • 2004
  • In: Chemical Physics. - : Elsevier BV. - 0301-0104 .- 1873-4421. ; 299:2-3, s. 157-161
  • Journal article (peer-reviewed)abstract
    • We have performed experiments where DKDP has been irradiated by short (100 fs), laser pulses. Subsequently X-ray pulses with a duration of 100 ps were used as a probe. Time-resolved X-ray diffraction enables monitoring of the transitions between the paraelectric and ferroelectric phases. By recording the intensity of a peak only present in the paraelectric phase, we observe indications of a phase-transition following laser-irradiation of DKDP in the ferroelectric phase. We have estimated the laser heating effect, by measuring the strain (peak shifts) in the diffraction patterns. Furthermore, the orientation of the ferroelectric domains has been observed. In spite of the fact that the temperature did not rise above the Curie temperature, following interaction with this radiation, the polarization of ferroelectric domains was modified. This indicates a mechanism where short pulses impulsively excite phonons. which enable either reversal of entire domains, the shift of domain walls and/or the broadening of the domain wall widths. (C) 2003 Elsevier B.V. All rights reserved.
  •  
7.
  • Sondhauss, Peter, et al. (author)
  • Picosecond X-ray studies of coherent folded phonons in a multiple quantum well
  • 2005
  • In: Physical Review Letters. - Lund Univ, Dept Phys, SE-22100 Lund, Sweden. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Malmo Univ, Sch Technol & Soc, S-20506 Malmo, Sweden. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. : AMERICAN PHYSICAL SOC. - 1079-7114 .- 0031-9007. ; 94
  • Journal article (peer-reviewed)abstract
    • Coherent folded acoustic phonons in a multilayered GaSb/InAs epitaxial heterostructure were generated by femtosecond laser pulses and studied by means of ultrafast x-ray diffraction. Coherent phonons excited simultaneously in the fundamental acoustic branch and the first back-folded branch were detected. This represents the first clear evidence for phonon branch folding based directly on the atomic motion to which x-ray diffraction is sensitive. From a comparison of the measured phonon-modulated x-ray reflectivity with simulations, evidence was found for a reduction of the laser penetration depth. This reduction can be explained by the self-modulation of the refractive index due to photogenerated free carriers.
  •  
8.
  • Sondhauss, Peter, et al. (author)
  • Time resolved X-ray diffraction and non-thermal inelastic X-ray scattering
  • 2004
  • In: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 705, s. 1387-1390
  • Conference paper (peer-reviewed)abstract
    • Atomic processes like e.g. molecular vibrations, chemical reactions or phase transitions happen on picosecond down to femtosecond time scales. Novel pulsed X-ray sources or alternatively ultrafast X-ray detectors allow the investigation of these processes in real time. A powerful tool for the investigation of the dynamics in crystalline materials is time resolved X-ray diffraction (TRXD). As an example the authors present the measurement of "phonon branch folding" in a GaSb/InAs superlattice by means of TRXD. In the second part we look forward to the near future of TRXD. X-ray scattering from coherent acoustic and optical phonons has recently become describable within the framework of dynamical diffraction theory. This theory provides the means for the detailed modeling of how various lattice dynamical processes manifest themselves in the diffracted X-ray signal. Simulations are presented showing the effects of coherent acoustic and optical phonons on the rocking curve of quartz (010)
  •  
9.
  • Vinuesa, Ricardo, et al. (author)
  • Documentation of the role of large-scale structures in the bursting process in turbulent boundary layers
  • 2015
  • In: Physics of fluids. - : American Institute of Physics (AIP). - 1070-6631 .- 1089-7666. ; 27:10
  • Journal article (peer-reviewed)abstract
    • The scaling of the bursting frequency with Reynolds number is investigated experimentally by means of hot-wire measurements in turbulent boundary layers over the range 1580 < ReΘ < 23 700. Bursting events are detected by means of the u-level technique, and the effect of filtering and the choice of the threshold are also assessed. We find that the inner scaling produces excellent collapse of the high-pass filtered data in the buffer and log regions, regardless of the cutofffrequency and the threshold. This is due to the fact that the high-pass filter attenuates the low frequency component of the streamwise velocity signal, which is associated with large-scale structures in the flow. On the other hand, the bursting frequency scales with outer variables when the time-series is low-pass filtered with very low cutofffrequencies, highlighting the connection between bursting phenomena and the outer flow.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-9 of 9

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view