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391.
Jukka Lempa 《Mathematical Methods of Operations Research》2008,67(2):257-268
The objective of this study is to provide an alternative characterization of the optimal value function of a certain Black–Scholes-type
optimal stopping problem where the underlying stochastic process is a general random walk, i.e. the process constituted by
partial sums of an IID sequence of random variables. Furthermore, the pasting principle of this optimal stopping problem is
studied.
相似文献
392.
Peter Sjövall Björn Johansson Peter Stenvinkel Jukka Lausmaa 《Applied Surface Science》2008,255(4):1177-1180
In this work, time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used for detecting systematic variations in the spatial and compositional distributions of lipids in human tissue samples. Freeze-dried sections of subcutaneous adipose tissue from six chronic kidney disease (CKD) patients and six control subjects were analysed by TOF-SIMS using 25 keV Bi3+ primary ions. Principal component analysis of signal intensities from different fatty acids, diacylglycerol and triacylglycerol ions showed evidence for systematic variations in the lipid distributions between different samples. The main observed difference in the spectra was a concerted variation in the signal intensities from the saturated lipids relative to the unsaturated lipids, while variations in the fatty acid chain lengths were considerably weaker. Furthermore, the three samples showing the lowest degree of saturation came from CKD patients, while three of the four samples with the highest degree of saturation were from control subjects, indicating that low saturation levels in the glycerol lipid distribution may be more frequent in patients with CKD. Systematic differences in the spatial distributions between saturated and unsaturated glycerol lipids were observed in several analysed areas. 相似文献
393.
Jatta E. Berberat Mikko J. Nissi Jukka S. Jurvelin Miika T. Nieminen 《Magnetic resonance imaging》2009
The interstitial water content typically increases in the early degeneration of articular cartilage. Previously, T2 relaxation has been related to water content, yet it is known to be strongly affected by the collagen orientation. Articular cartilage plugs from the bovine patella, femur and tibia (N=20) were mapped for T1 and T2 at 9.4 T to test the ability of T1 relaxation to reflect cartilage water content. As a reference, water and proteoglycan (PG) contents were determined. Significant (P<.01) linear associations were demonstrated between the relaxation rates and tissue water content (R1: r=−.81, R2: r=−.60) and PG content (R1: r=.75). After adjustment for the tissue water content, partial correlation analysis did not show significant associations between the relaxation rates and tissue PG content. After the effect of PGs was removed, significant (P<.05) linear correlation between the relaxation rates and tissue water content (R1: r=−.48, R2: r=−.50) was observed. Thus, the spin-lattice relaxation rate is proposed to provide a biomarker for water content in articular cartilage. 相似文献
394.
Johanna Sepp 《Fresenius' Journal of Analytical Chemistry》1960,176(6):464
Ohne Zusammenfassung 相似文献
395.
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398.
Johanna Sepp 《Fresenius' Journal of Analytical Chemistry》1960,175(2):125
Ohne Zusammenfassung 相似文献
399.
400.
Ursula Baumann H. Garschagen K. Cruse und Johanna Sepp 《Fresenius' Journal of Analytical Chemistry》1960,178(1):76-79
Ohne Zusammenfassung 相似文献