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background & aim: stroke in young adults is rare but can be devastating for the affected individuals and their families. some triggers of stroke may be acute but transient effects on the pathophysiological condition while other factors may be effective overa longer period. methods & materials: this study was a case-crossover study on 18 young adults. the study included patients aged 15-49 years...

We calculate the eigenspectrum of random walks on the Eden tree in two and three dimensions. From this, we calculate the spectral dimension ds and the walk dimension dw and test the scaling relation ds = 2df/dw (= 2d/dw for an Eden tree). Finite-size induced crossovers are observed, whereby the system crosses over from a short-time regime where this relation is violated (particularly in two dim...