Transient molecular networks, a class of adaptive soft materials with remarkable application potential, display complex, and intriguing dynamic behavior. By performing dynamic light scattering on a wide angular range, we study the relaxation dynamics of a reversible network formed by DNA tetravalent nanoparticles, finding a slow relaxation mode that is wave vector independent at large q and crosses over to a standard q^{-2} viscoelastic relaxation at low q. Exploiting the controlled properties of our DNA network, we attribute this mode to fluctuations in local elasticity induced by connectivity rearrangement. We propose a simple beads and springs model that captures the basic features of this q^{0} behavior.

The addition of pseudocereal flours to semolina is becoming more and more popular to improve the nutritional quality of the resultant pasta. The aim of this study was the evaluation of several properties of commercial pasta made from a mixture of buckwheat flour and durum wheat semolina. The characterisation of products, belonging to different producers, focused on the evaluation of chemical and physical properties, such as water uptake and mechanical properties before and after cooking and surface characteristics. A sensory analysis was also performed in order to evaluate firmness, resistance to breaking and overall acceptability. The results highlighted high heterogeneity of the mechanical properties, solid loss and water absorption among the samples. The great variability could be explained by the different processing conditions adopted by each producer, particularly by the procedure used to form and shape the dough into the final product.

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