| 1. |
- Bjordal, K, et al.
(author)
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A 12 country field study of the EORTC QLQ-C30 (version 3.0) and the head and neck cancer specific module (EORTC QLQ-H&N35) in head and neck patients
- 2000
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In: European Journal of Cancer. - 1879-0852. ; 36:14, s. 1796-1807
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Journal article (peer-reviewed)abstract
- This study tests the reliability and validity of the European Organization for Research and Treatment of Cancer (EORTC) head and neck cancer module (QLQ-H&N35) and version 3.0 of the EORTC Core Questionnaire (QLQ-C30) in 622 head and neck cancer patients from 12 countries. The patients completed the QLQ-C30, the QLQ-H&N35 and a debriefing questionnaire before antineoplastic treatment or at a follow-up. 232 patients receiving treatment completed a second questionnaire after treatment. Compliance was high and the questionnaire was well accepted by the patients. Multitrait scaling analysis confirmed the proposed scale structure of the QLQ-H&N35. The QLQ-H&N35 was responsive to differences between disease status, site and patients with different Karnofsky performance status, and to changes over time. The new physical functioning scale (with a four-point response format) of version 3.0 of the QLQ-C30 was shown to be more reliable than previous versions. Thus, the QLQ-H&N35, in conjunction with the QLQ-C30, appears to be reliable, valid and applicable to broad multicultural samples of head and neck cancer patients.
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| 2. |
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| 3. |
- Björk, Gunnar, et al.
(author)
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A theory of the relative phase and number difference of two quantized harmonic oscillators
- 2002
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In: Physica Scripta. - 0031-8949 .- 1402-4896. ; T102, s. 133-146
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Journal article (peer-reviewed)abstract
- We present a comprehensive and self-consistent theory of relative-phase measurements and the associated Hermitian relative-phase operator of two harmonic oscillators. We find that since Nature does not favor any particular initial condition of the two oscillators, the relative-phase operator is not unique. We show that the relative-phase eigenstates; are maximally entangled. Therefore. most relative-phase operators lack a classical correspondence, even in the high-excitation limit. Furthermore, we find that the relative phase and the excitation number difference are noncommuting, noncanonical observables and we derive a commutation relation.
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| 4. |
- Björk, Gunnar, et al.
(author)
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Entangled-state lithography : Tailoring any pattern with a single state
- 2001
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 86:20, s. 4516-4519
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Journal article (peer-reviewed)abstract
- We demonstrate a systematic approach to Heisenberg-Limited lithographic image formation using four-mode reciprocal binomial states. By controlling the exposure pattern with a simple bank of birefringent plates, any pixel pattern on a (N + 1) X (N + 1) grid, occupying a square with the side half a wavelength long, can be generated from a 2N-photon state.
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| 5. |
- Björk, Gunnar, et al.
(author)
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Hilbert space factorization and partial measurements
- 2003
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In: Optics and Spectroscopy. - : Pleiades Publishing Ltd. - 0030-400X .- 1562-6911. ; 94:5, s. 695-699
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Journal article (peer-reviewed)abstract
- A quantum system whose state vector belongs to a finite-dimensional Hilbert space is considered. If this space has a dimension that is a composite number, one can factor the space into a tensor product of subspaces. An observable that acts only in one of these subspaces is called a partial measurement. Some of the properties and the interpretation of such partial measurements are discussed.
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| 6. |
- Björk, Gunnar, et al.
(author)
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Subwavelength lithography over extended areas
- 2001
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 6401:1
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Journal article (peer-reviewed)abstract
- We demonstrate a systematic approach to subwavelength resolution Lithographic image formation on films covering areas larger than a wavelength squared. For example, it is possible to make a lithographic pattern with a feature size resolution of lambda/[2(N+1)] by using a particular 2M-photon, multimode entangled state, where N less than or equal toM, and banks of birefringent plates. By preparing such a statistically mixed state, one can form any pixel pattern on a 2(M-N)(N+1) x 2(M-N)(N+1) pixel grid occupying a square with side L = 2(M-N-1)lambda. Hence, there is a trade off between the exposed area, the minimum lithographic feature size resolution, and the number of photons used for the exposure. We also show that the proposed method will work even under nonideal conditions, albeit with somewhat poorer performance.
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| 7. |
- Björk, Gunnar, et al.
(author)
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Visibility is not a good measure of a well-defined relative phase
- 2000
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 6202:2
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Journal article (peer-reviewed)abstract
- In a recent paper Marburger and Das [J. H. Marburger III and K. K. Das, Phys. Rev. A 59, 2213 (1999)] considered an interference visibility experiment involving two weakly interacting Bose-Einstein condensates. It was shown that condensate eigenstates of the Hermitian relative phase operator do not give interference fringes with unit visibility in a Young's double slit type of experiment. The authors concluded that ... these states are not especially well suited to describe weakly interacting multiply occupied coherent bosonic systems. In this work we suggest a criterion for states with a well-defined relative phase. Subsequently we show that the relative phase operator eigenstates satisfy this criterion. This suggests that the concept of interference visibility can, and should, be generalized, since it is widely believed that interference visibility is a measure of the relative phase properties. We therefore propose a broader, but still operational, definition of interference visibility, which we call generalized visibility, and prove that the relative phase operator eigenstates indeed can show unit generalized visibility. We also derive a simple, but general, criterion for states which can display a unit generalized visibility. Somewhat surprisingly, this criterion is weaker than the criterion for a well-defined relative phase. Finally, we discuss which two-mode states can display unit (ordinary) visibility.
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| 8. |
- Emami, N., et al.
(author)
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Effect of light power density variations on bulk curing properties of dental composites
- 2003
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In: Journal of Dentistry. - : Elsevier BV. - 0300-5712 .- 1879-176X. ; 31:3, s. 189-196
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Journal article (peer-reviewed)abstract
- Objective. The hypothesis that low light intensity and long but sufficient curing time can produce composites with volumetric shrinkage, degree of conversion (DC%) and Young's modulus (E-modulus) comparable to those of high light intensity cured composite was tested, when the contraction strain and heat generation were lower with Low Light intensity curing. Methods. Dental composites (Z100 and Z250, 3M ESPE) were investigated. Specimens were cured with Light intensities of 200, 450 and 800 mW/cm(2) for 140, 60 and 35 s from a distance of 7 mm. Strain-gages were used for contraction strain measurements. DC% was measured at the top and the bottom of 4 mm thick samples using FT-Raman spectroscopy. Volumetric polymerization shrinkage was determined using a water displacement method. E-modulus was determined in tension on composite specimens. Results. The results were analyzed using ANOVA and Duncan's multiple range tests and regular t-test. Polymerization stress Level decreased significantly (p < 0.05) when cured with 200 mW/cm(2) rather than with 800 mW/cm(2). Temperature rises were significantly different (p < 0.05) for different composites and light intensity values. Reduction in light intensity did not decrease the DC% values significantly at the top surfaces. The most dramatic differences existed between top and bottom surfaces (p < 0.05) rather than among curing groups. Measured E-modulus and volumetric shrinkage values were not significantly different (p > 0.05) between different light intensity groups. Conclusion. DC%, E-modulus and the volumetric shrinkage values in cured composites were not affected by low Light intensity, however, the contraction strain and polymerization's exotherm were decreased. Thus our results support the proposed hypothesis. Published by Elsevier Science Ltd.
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| 9. |
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| 10. |
- Hessmo, B., et al.
(author)
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Entangled states in interferometry
- 2002
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In: Acta Physica Polonica. A. - 0587-4246 .- 1898-794X. ; 101:1, s. 37-46
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Journal article (peer-reviewed)abstract
- We show how some entangled quantum states can be used to improve interferometric measurements. We describe why Schrodinger-cat states are very sensitive to relative-phase shifts and why relative-phase states as described by A. Luis and L.L. Sanchez-Soto resolve the interval [0, 2pi] well. We also describe how the quantum concept of well-defined relative-phase and the classical visibility of an interference pattern are related.
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