Trifactorial interactive effects of nutrients, water potential and temperature on carbohydrate allocation to the embryonic axis of desert plant seeds

Seeds ofProsopis juliflora, Calotropis proceraandSorghum × drummondiiseeds were subjected to trifactorial treatment combinations of: nutrients (Nr), temperature (T) and reduced water potential (ψ_m) in their incubation medium. The embryonic axis and storage tissue of germinating seeds were analysed for soluble sugars (SS) and hydrolysable carbohydrates (HC). Allocation of both carbon fractions in germinating seed organs was variously affected by single factors and their mutual interactions. Differences in such effects included both magnitude and relative role of each factor or interaction, the effect also being organ and/or species dependent. The interaction φ_m× T had the predominant role in changes of both SS and HC content and their allocation in seed organs, while the interaction Nr × φ_m× T had a subdominant role. Nutrients in the medium generally induced significantly higher SS and HC content in whole seeds at low water potentials, the level of which is temperature dependent (indicating interactive effects between single factors). Also, nutrients generally increased translocation of SS to the radicle (hence, allocation of HC), improving its capacity of water uptake through increased osmolarity.     

North east pacific time-integrated undersea networked experiments (NEPTUNE): cable switching and protection

The objective of the North East Pacific Time-Integrated Undersea Networked Experiments (NEPTUNE) is to establish a permanent, subsea observatory surrounding the Juan de Fuca tectonic plate. To achieve this objective, a special power distribution system is designed to provide continuous power to science equipment, vehicles, and laboratories located as deep as 5 km below the water surface. The NEPTUNE power system is significantly different from terrestrial power systems in many aspects and it requires different switching, protection, and control strategies. In this paper, we address the design of system switching and fault isolation equipment.