| 1. |
- Lopez, Rodrigo, et al.
(författare)
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Time-resolved ellipticity gating of high-order harmonic emission
- 2004
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Ingår i: Physical Review A. ; 69, s. 1-053811
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Tidskriftsartikel (refereegranskat)abstract
- We present time-resolved cross-correlation measurements of extreme ultraviolet (xuv) pulses generated as high-order harmonics of intense 35 fs pulses, using a short (12 fs) probe pulse. We modulate the ellipticity of the laser driving the generation process such that the polarization is linear for short times around the temporal peak of the pulse. Since harmonic generation is strongly suppressed for very small amounts of driving laser ellipticity, the emission of xuv radiation can therefore be confined to times much shorter than the laser pulse duration. In addition, our setup allows us to continuously confine the xuv emission as well as to determine its frequency sweep during the pulse.
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| 2. |
- Zair, A, et al.
(författare)
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Time-resolved measurements of high order harmonics confined by polarization gating
- 2004
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Ingår i: Applied Physics B. - : Springer Science and Business Media LLC. - 0946-2171 .- 1432-0649. ; 78:7-8, s. 869-872
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the temporal confinement of high order harmonic pulses generated by a femtosecond (fs) infrared (IR) pulse with a time varying polarization. We use a set of two birefringent quartz plates to modulate the IR polarization. It produces a short temporal gate of linear polarization where harmonics are efficiently generated during a small fraction of the IR pulse. By rotating one of the plates, the gate width can be continuously varied between 70 fs down to 7 fs. The XUV pulse duration is measured by cross-correlation with a probe IR pulse of 12 fs. When the gate width is decreased, a clear temporal confinement of the XUV emission is observed through the cross correlation signal. This experiment is the first direct experimental evidence in the temporal domain that the polarization gating technique can be used to significantly shorten the harmonic pulse duration.
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| 3. |
- Atroshi, I, et al.
(författare)
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Quality of life after hip revision with impaction bone grafting on a par with that 4 years after primary cemented arthroplasty
- 2004
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Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 75:6, s. 677-683
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Tidskriftsartikel (refereegranskat)abstract
- Background There have been few studies evaluating patient-reported quality of life outcomes after hip revision with impaction bone grafting. Patients and methods The inclusion criteria were aseptic loosening after primary arthroplasty performed for osteoarthrosis, and first-time revision with impacted morselized allograft bone and cemented Exeter stem. During a 4-year period, 35 patients were eligible and all were included. The Nottingham Health Profile (NHP) was completed by the patients and the Charnley hip scores recorded by the examining surgeon preoperatively, after 6 months and yearly up to 4 years (28 patients) postoperatively. For comparison, 35 osteoarthrotic patients completed the NHP 4 years after cemented Exeter primary arthroplasty. Results At 4 years, the NHP scores for the revision patients did not differ significantly from those recorded in the primary arthroplasty group. Among the revision patients, mixed model analysis showed improvement in NHP pain (p < 0.001) and physical mobility scores (p = 0.002). The effect size at 4 years was large for pain (1.2) and moderate for physical mobility (0.6). The major improvement was recorded at 6 months, with no further substantial change observed. The correlations between the NHP and Charnley scores were weak or moderate (r, -0.15 to -0.67). Interpretation Hip revision with impaction bone grafting leads to substantially improved quality of life, similar to that 4 years after primary arthroplasty.
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| 4. |
- Sundström, L. Fredrik, 1972, et al.
(författare)
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Hatchery selection promotes boldness in newly hatched brown trout (Salmo trutta): implications for dominance
- 2004
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Ingår i: Behavioral Ecology. - : Oxford University Press (OUP). - 1045-2249 .- 1465-7279. ; 15:2, s. 192-198
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Tidskriftsartikel (refereegranskat)abstract
- By using newly hatched (approximately 2 weeks old) brown trout (Salmo trutta) from six families of wild and six families of sea-ranched origin (seventh generation), we tested the hypotheses that (1) the hatchery environment selects for increased boldness, and (2) boldness predicts dominance status. Sea-ranched trout spend their first 2 years in the hatchery before being released into the wild at the onset of seaward migration. Trout were presented with a novel object (tack) and with food (brine shrimp), and their responses were measured and scored in terms of boldness. Siblings with increasing difference in boldness were then paired in dyadic contests. Fish of sea-ranged origin were on average bolder than were fish of wild origin, and bolder individuals were more likely to become dominant regardless of origin. Boldness was not related to RNA levels, indicating that bold behavior was not a consequence of higher metabolism or growth rate. Neither was size a predictor of bold behavior or the outcome of dyadic contests. These results are consistent with studies on older life stages showing increased boldness toward predators in hatchery-selected fish, which suggests that behavioral consequences of hatchery selection are manifested very early in life. The concordance between boldness and dominance may suggest that these behaviors are linked in a risk prone-aggressive phenotype, which may be promoted by hatchery selection. However, we also found significant variation in behavioral and growth-related traits among families, suggesting that heritable variation has not been exhausted by sea-ranching procedures.
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