| 1. |
- Akhmediev, N.N., et al.
(författare)
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Radiationless optical solitons with oscillating tails
- 1994
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Ingår i: Optics Communications. - : Elsevier BV. - 0030-4018. ; 110:5-6, s. 540-544
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Tidskriftsartikel (refereegranskat)abstract
- We investigate, analytically and numerically, stationary soliton-like pulse propagation in nonlinear optical fibres, taking into account the effects of fourth order dispersion. A new type of stationary stable soliton-like solution is found. A unique feature of this type of solution is their unusual asymptotic behaviour (oscillating tails). © 1994.
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| 2. |
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| 3. |
- Andersson, Dan, 1966, et al.
(författare)
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Wave-breaking-free pulses in nonlinear-optical fibers
- 1993
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Ingår i: Journal of the Optical Society of America B: Optical Physics. - 1520-8540 .- 0740-3224. ; 10:7, s. 1185-1190
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Tidskriftsartikel (refereegranskat)abstract
- A qualitative as well as quantitative investigation is made of the conditions for avoiding wave breaking during pulse propagation in optical fibers. In particular, it is shown that pulses having a parabolic intensity variation are approximate wave-breaking-free solutions of the nonlinear Schrodinger equation in the high-intensity limit. A simple expression for the compression factor of a fiber-grating compressor based on parabolic pulses is also derived.
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| 4. |
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| 5. |
- Ankiewicz, A., et al.
(författare)
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Dark soliton pairs in fiber couplers
- 1994
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Ingår i: Optics Communications. - 0030-4018. ; 111:1-2, s. 116-122
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Tidskriftsartikel (refereegranskat)abstract
- We analyze the possible stationary states formed by pairs of dark solitons propagating in dual-core optical fibers, i.e. in a nonlinear coupler. These are local disturbances on a constant background. We find new dark soliton states, characterize them and show that they differ from the soliton states consisting of coupled bright solitons in several ways. © 1994.
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| 6. |
- Brandt, Lennart, et al.
(författare)
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Myelography in the late postoperative period in patients subjected to anterior cervical decompression and fusion
- 1993
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Ingår i: Acta Neurochirurgica. - 0001-6268. ; 122:1-2, s. 97-101
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Tidskriftsartikel (refereegranskat)abstract
- During a 13 year period, 286 patients with cervical disc herniation and/or spondylotic spurs, were subjected to anterior decompression and vertebral interbody fusion with autologous bone. Twenty patients were re-admitted in the late postoperative period due to recurrent radicular symptoms and/or signs of myelopathy. In these patients myelography was performed again. In 14 patients spinal cord compression and/or nerve root involvement at a new level was visualized. At the operated level, however, the myelograms demonstrated a smooth anterior wall in the spinal canal. The series confirms the safety, effectiveness and reliability of the Cloward procedure in achieving long term spinal cord and nerve root decompression, and a solid vertebral interbody fusion.
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| 7. |
- Düppe, Henrik, et al.
(författare)
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Long-term results of fracture of the scaphoid. A follow-up study of more than thirty years
- 1994
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Ingår i: Journal of Bone and Joint Surgery. American Volume. - 1535-1386. ; 76:2, s. 249-252
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Tidskriftsartikel (refereegranskat)abstract
- Fifty-six patients who had had a fracture of the scaphoid from January 1950 through December 1959 were interviewed, re-examined, and had radiographs made of both hands an average of thirty-six years (range, thirty-one to forty years) later. The average age at the time of the treatment was twenty-eight years (range, fifteen to forty-five years). Fifty-two of the fifty-six patients were treated at the time of the fracture; the other four had a non-union when first seen. The rate of non-union for the fresh fractures at the most recent follow-up examination was 10 per cent (five of fifty-two). Dorsal intercalated-segment instability was found in three of the fifty-six patients; all three had a pseudarthrosis and manifest radiocarpal osteoarthrosis. Marked radiocarpal osteoarthrosis developed in only one (2 per cent) of the forty-seven patients who had a healed fracture; it was far more common in the group that had a pseudarthrosis, in which the prevalence was five of nine patients. Manifest osteoarthrosis also seemed to be associated with pain or weakness: it had developed in only three (6 per cent) of the forty-nine patients who did not have any symptoms at the re-examination, compared with three of the seven who had symptoms.
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| 8. |
- Höök, Anders, 1962, et al.
(författare)
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Soliton instabilities and pulse compression in minimum dispersion fibers
- 1994
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Ingår i: IEEE Journal of Quantum Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9197 .- 1558-1713. ; 30:8, s. 1831-1841
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Tidskriftsartikel (refereegranskat)abstract
- A new stability of ultrashort pulses in optical fibers is demonstrated which, together with a recently discovered modulation instability, is shown to deteriorate a pulse compression mechanism. The pulse compression is analyzed in detail by means of a perturbation technique.
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| 9. |
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| 10. |
- Josefsson, Per Olof, et al.
(författare)
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Closed treatment of Jones fracture. Good results in 40 cases after 11-26 years
- 1994
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Ingår i: Acta Orthopaedica Scandinavica. - : Medical Journals Sweden AB. - 0001-6470. ; 65:5, s. 545-547
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Tidskriftsartikel (refereegranskat)abstract
- 40 patients with transversal or short oblique fractures of the proximal shaft of the fifth metatarsal bone (Jones fracture) were treated with full weight bearing with or without elastic bandage in 39 cases and plaster cast immobilization in one. 24 cases were acute traumatic fractures, 14 stress fractures and 2 refractures. After 17 (11-26) years, 33 of the fractures had healed primarily, evidence of refracture or delayed union was found in 7 and there were no non-unions. All but one of the patients were free of symptoms.
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