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Water distribution networks (WDNs) are complex combinations of nodes and links, and the current tendency is to modify their topological structure through the closure of isolation valves for monitoring and water quality reasons. For their analysis, several approaches based on graph theory have recently been proposed, mainly considering steady‐state flow conditions. However, in their real functioning, WDNs are continuously subjected to pressure transients generated by maneuvers on regulation devices or by users' activity. This study investigates the application of some metrics from graph theory, already used in the context of steady‐state analysis, for assessing the effects of changes in the topological structure of a network—due for example, to sectorization or branching operations—on its transient response when subjected to maneuvers on devices such as hydrants, pumps, etc. or users' activity. The analysis shows that some connectivity metrics can effectively reflect the dynamic pressure behavior of the network and, thus, provide useful indications for design and management operations taking into account unsteady flow features. Key Points: Analysis of changes in the transient response of a Water Distribution Network (WDN) due to topological structure modificationsApplication of Connectivity Metrics (CMs) for characterizing the transient response of a WDNAnalysis of the pro and cons of different CMs in reflecting the dynamic behavior of a WDN [ABSTRACT FROM AUTHOR]

At the Water Engineering Laboratory of the University of Perugia, Italy, a wide experimental program has been carried out in a polymeric pipe network with two 100 × 100 m square loops. The aim of this program is to analyze the dynamic response of the system to transients caused by a change in water consumption. To emphasize such a response, transients are generated by the complete and fast closure of an end‐user, located at the downstream end of a service line. During tests, the combined effect of simultaneous consumers, whose consumption is varied both deterministically and stochastically, has been analyzed. The tests allow examining the propagation of the generated pressure waves within the network for different water consumption variations and end‐user locations. The lessons learnt from the experimental results may help the water utility managers to identify the reasons for the higher frequency of occurrence and severity of faults in some specific portions of water distribution networks apparently "similar" to others where damages are less frequent and severe. Key Points: Several laboratory transient tests are carried out in a polymeric looped water distribution network (WDN) due to deterministic and stochastic consumption variationsThe results may help the water utilities to identify the reasons for the high occurrence and severity of faults in some portions of WDNsThe reasons for faults may be repetitive and fast consumption changes, especially at night, and a high small‐diameter pipe percentage [ABSTRACT FROM AUTHOR]

BSTRACT: Wheat sprouts contain a remarkable level of various antioxidants. A fraction containing high amounts of powerful antioxidant glycoside molecules has been isolated. In a dose-dependent manner, this fraction reduces the lucigenin-amplified chemiluminescence produced by the superoxide anion generated from the xanthine/xanthine oxidase system, thus indicating a superoxide-scavenging activity. A protective effect of this wheat sprouts fraction on the oxidative damage of pBR322 plasmid DNA induced by Fenton reaction (Fe2+/H2O2) was subsequently demonstrated. Moreover, the results reported here show that the amount of antioxidant compound strongly increases during the germination phase, while scantly present in the wheat germ, and virtually absent in the young wheat plant. [ABSTRACT FROM AUTHOR]