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H. Dekker 《Physica A》1978,94(2):339-353
The unambiguous continuous functional integral representation of general diffusion processes will be derived by means of a transformation invariant Fourier series analysis of the alternate paths between specified endpoints. Previous results from Stratonovich, Horsthemke and Bach, and Graham will be confirmed, while deeper insight is gained into the limit of continuity in functional integration.  相似文献   
35.
Separation of nucleoside mixtures on Dowex-1 (OH-)   总被引:3,自引:0,他引:3  
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H. Dekker 《Physics letters. A》1985,112(5):197-200
Kramers' model for equilibrium via noise activated escape over a potential barrier is considered as an eigenvalue problem. Using Rayleigh's identity for the pertinent eigenvalue, the escape rate is obtained for a bistable system with a smooth parabolic barrier.  相似文献   
37.
Human 15‐lipoxygenase‐1 (15‐LOX‐1) belongs to the class of lipoxygenases, which catalyze oxygenation of polyunsaturated fatty acids, such as arachidonic and linoleic acid. Recent studies have shown that 15‐LOX‐1 plays an important role in physiological processes linked to several diseases such as airway inflammation disease, coronary artery disease, and several types of cancer such as rectal, colon, breast and prostate cancer. In this study, we aimed to extend the structural diversity of 15‐LOX‐1 inhibitors, starting from the recently identified indolyl core. In order to find new scaffolds, we employed a combinatorial approach using various aromatic aldehydes and an aliphatic hydrazide tail. This scaffold‐hopping study resulted in the identification of the 3‐pyridylring as a suitable replacement of the indolyl core with an inhibitory activity in the micromolar range (IC50=16±6 μm ) and a rapid and efficient structure–activity relationship investigation.  相似文献   
38.
We report the fabrication and performance of the first C-band directly written monolithic waveguide laser (WGL). The WGL device was created in an erbium- and ytterbium-doped phosphate glass host and consisted of an optical waveguide that included a distributed feedback Bragg grating structure. The femtosecond laser direct-write technique was used to create both the waveguide and the waveguide-Bragg grating simultaneously and in a single processing step. The waveguide laser was optically pumped at approximately 980 nm and lased at 1,537 nm with a bandwidth of less than 4 pm.  相似文献   
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Using femtosecond laser writing, optical waveguides were monolithically integrated into a commercial microfluidic lab-on-a-chip device, with the waveguides intersecting a microfluidic channel. Continuous-wave laser excitation through these optical waveguides confines the excitation window to a width of 12 microm, enabling high-resolution monitoring of the passage of different types of fluorescent analytes when migrating and being separated in the microfluidic channel by microchip capillary electrophoresis. Furthermore, we demonstrate on-chip-integrated waveguide excitation and detection of a biologically relevant species, fluorescently labeled DNA molecules, during microchip capillary electrophoresis. Well-controlled plug formation as required for on-chip integrated capillary electrophoresis separation of DNA molecules, and the combination of waveguide excitation and a low limit of detection, will enable monitoring of extremely small quantities with high spatial resolution.  相似文献   
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This paper discusses several strategies for the maintenance of light-standards, where each light-standard consists of n independent and identical lamps screwed on a lamp assembly. The lamps are subject to stochastic failures, and must be correctly replaced if the number of failed lamps reaches a prespecified number m, a norm that is set by the local management to guarantee a minimum luminance. As lamps have an increasing hazard rate and there is a fixed cost of hoisting the assembly, we propose various variants of the m-failure group replacement rule which have in particular an age-criterion to indicate which of the non-failed lamps must be preventively replaced at the time that the assembly is lowered for a corrective lamp replacement. We show how the optimal threshold age can be determined. It appears that this modification reduces the long run average maintenance cost of the Europe Combined Terminals by approximately 8.3%.  相似文献   
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