The amyloid fibrils of amyloid β protein (Aβ) from Alzheimer's disease are likely to show the cytotoxicity, depending on their morphology. The relationship between the nucleation kinetics of the Aβ fibrils and their morphology has been investigated. From the perspective of a crystallization technique assuming primary/secondary nucleation steps and an elongation step, the secondary nucleation rate B [# m−3 s−1], was experimentally and coarsely determined by using total internal reflection fluorescence microscopy combined with thioflavin T. In an aqueous solution, linear and rigid fibrils were formed with a relatively smaller B value ((2.83 ± 0.55) × 105 # m−3 s−1), whereas spherulitic amyloid assemblies were formed in the presence of negatively charged liposome including oxidized lipids, with a larger B value ((7.65 ± 0.47) × 105 # m−3 s−1). Those findings should lead to a better understanding of the mechanism for the formation of fibrils and senile plaques in Alzheimer's disease. © 2012 American Institute of Chemical Engineers AIChE J, 2012

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The Kinematic Driver-Aerosol (KiD-A) intercomparison was established to test the hypothesis that detailed warm microphysical schemes provide a benchmark for lower-complexity bulk microphysics schemes. KiD-A is the first intercomparison to compare multiple Lagrangian cloud models (LCMs), size bin-resolved schemes, and double-moment bulk microphysics schemes in a consistent 1D dynamic framework and box cases. In the absence of sedimentation and collision-coalescence, the drop size distributions (DSDs) from the LCMs exhibit similar evolution with expected physical behaviors and good inter-scheme agreement, with the volume mean diameter (Dvol ) from the LCMs within 1 to 5% of each other. In contrast, the bin schemes exhibit non-physical broadening with condensational growth. These results further strengthen the case that LCMs are an appropriate numerical benchmark for DSD evolution under condensational growth. When precipitation processes are included, however, the simulated liquid water path, precipitation rates, and response to modified cloud drop/aerosol number concentrations from the LCMs vary substantially, while the bin and bulk schemes are relatively more consistent with each other. The lack of consistency in the LCM results stems from both the collision-coalescence process and the sedimentation process, limiting their application as a numerical benchmark for precipitation processes. Reassuringly, however, precipitation from bulk schemes, which are the basis for cloud microphysics in weather and climate prediction, is within the spread of precipitation from the detailed schemes (LCMs and bin). Overall, this intercomparison identifies the need for focused effort on the comparison of collision-coalescence methods and sedimentation in detailed microphysics schemes, especially LCMs.

A nanoparticle-embedded carbon nanofiber (PECNF) was proposed as a promising support of the Pd nanoparticle catalyst for formic acid oxidation reaction (FAOR). The nanofiber supports contained different weight and different nanoparticle were prepared by the electrospinning of polyacrylonitrile (PAN) by adding the nanoparticles, TiO2: TECNF, SiO2: SECNF and carbon black: CECNF, followed by carbonization and steam activation of the nanofiber. Cyclic voltammetry (CV) revealed a significantly high FAOR activity for the Pd/SECNF [1.00], which showed “muskmelon” like structure. Moreover, the chronoamperometory (CA) revealed a higher durability of the Pd/PECNF than that of Pd/CNF. Especially, Pd/SECNF [0.50] showed excellent durability. Based on these results, it was found that the SECNF is a promising support of the Pd for the DFAFC anode.

The fibril growth behavior of amyloid β protein (Aβ) on cell membranes is relating to the progression of Alzheimer's disease. This growth behavior of Aβ fibrils is sensitively affected by the metal ions, neurotransmitters, or bioreactive substrate. The inhibitory effect of those materials was quantitatively estimated from the viewpoints of "crystal growth". In a bulk aqueous solution, copper (II) ion showed the strong inhibitory effect on the growth of Aβ fibrils. Meanwhile, the addition of a closed-phospholipid bilayer membrane (liposome) could reduce the above inhibitory effect of copper (II) ion.