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Background
Amyotrophic lateral sclerosis (ALS) is an age-dependent neurodegenerative disease that causes motor neuron degeneration, paralysis and death. Mutations in Cu, Zn superoxide dismutase (SOD1) are one cause for the familial form of this disease. Transgenic mice expressing mutant SOD1 develop age-dependent motor neuron degeneration, skeletal muscle weakness, paralysis and death similar to humans. The mechanism whereby mutant SOD1 induces motor neuron degeneration is not understood but widespread mitochondrial vacuolation has been observed during early phases of motor neuron degeneration. How this vacuolation develops is not clear, but could involve autophagic vacuolation, mitochondrial permeability transition (MPT) or uncharacterized mechanisms. To determine which of these possibilities are true, we examined the vacuolar patterns in detail in transgenic mice expressing mutant SOD1G93A. 相似文献22.
In order to characterise chatter marks, in this work, various ground samples are investigated by means of two different optical surface analysis techniques: by using a confocal white light microscope and an angle-resolved light scattering sensor, respectively. The latter is also applied to an industrial belt grinding process in both roughness- and waviness-modes of measuring. These in-process measurements are found in good agreement with those of visual counting. Data processing in terms of the Fourier transformation it is shown to equally well accesses the wavelength of chatter marks in both roughness- and waviness-modes. Therefore it is concluded that chatter marks occurring during the industrial belt grinding can be seen as a superposition of roughness changes and waviness. 相似文献
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G. Ooms C. Poelma P. Poesio MJ.B.M. Pourquie J. Westerweel 《International Journal of Multiphase Flow》2008
In an earlier publication some of the authors presented a theoretical model for the calculation of the influence of particle inertia and gravity on the turbulence in a stationary particle-laden flow. In the present publication the model is extended for application to a decaying suspension. Also a comparison is given between predictions made with the model and experimental data (own data and data reported in the literature) on a decaying turbulent flow with particles in a water tunnel or in a wind tunnel. For most of the experiments a prediction with reasonable accuracy and an interpretation is possible by means of the model. 相似文献
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We analyse the evolution of a two-stage chemical reaction betweentwo neighbouring plumes of reactants. Under the assumption thatthe plumes are approximately Gaussian we derive a system ofordinary differential equations for the total amount, the centroidand the variance of each reactant. We compare the solution ofthese equations with full numerical simulation of the reaction.Excellent agreement is obtained, with solution of the near-Gaussianmodel requiring considerably less computational effort thanthe full simulations. Of key importance is the yield of thereaction, and we discuss this feature in particular. 相似文献
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We present a novel optofluidic device for non-invasive and label-free determination of liquid concentrations. A microfluidic channel filled with the sample solution is hit by laser light in an angle close to the critical angle for total internal reflection. Due to the intentionally defined divergence of the incident beam, parts of the rays will experience total internal reflection while another part will be transmitted. Both reflected and transmitted light signals are recorded and the ratio of these signals is used for sample characterization. The stability compared to single signal analyses is significantly improved, resulting in a resolution of approximately 40 mmol L(-1). The typical working range of the device under investigation is between a few tens of mmol L(-1) and 5 mol L(-1) making it useful for applications in the food industry, for example to determine the amount of phosphates in liquid products. 相似文献