Future of GaN RF Technology in Europe
In the last years GaN has remained a key technology in Europe in particular, but not only, for RF Applications. After an intensive period of research and development the scope has shifted towards industrialization and product development. This is especially true for the applications up to around 20GHz where systems are now being built using European GaN-based components. At the same time, an increasing part of the research activity has moved toward higher frequencies beyond 20GHz.
Power Amplification and Integration Challenges of Reconfigurable Antennas for Space Applications
This paper reviews critical technologies for spaceborne active antennas. Focus is put on high-power amplification concepts, solutions for improved thermal management and other key areas that drive the performance of active antennas today. Preliminary results from associated ESA R&D activities are presented as well.
Comparative studies of α-Lactalbumin and lysozyme: Echidna lysozyme
Summaryα-Lactalbumin is a modifier protein for galactosyl transferase in the biosynthesis of lactose and lysozyme catalyses the cleavage of β(1–4) glycosidic linkages. It is now generally believed that α-lactalbumin and lysozyme have diverged from a common ancestor. Comparative studies of these proteins from several species are reported here.The presence of lactose and lactose synthetase activity is shown in mature milk samples from a variety of placental mammals (eutheria) and a pouch bearing mammal (marsupialia). The isolation of the α-lactalbumins involved and their properties are compared.The position is different in the milk samples of monotremes. The α-lactalbumin, lactose and lactose synthetase activity levels in the two platypus samples studied are very low. The levels of lactose and lactose synthetase activity in some echidna(Tachyglossus aculeatus) samples are low, but appreciable in others. No α-lactalbumin is present. The lysozyme activity is appreciable, some samples containing a different lysozyme from that present in others. One of these (designated echidna lysozyme I) is capable of lactose synthetase modifier activity in the presence of bovine “A protein”.The properties of this lysozyme are compared with those of lysozymes and α-lactalbumins from a variety of species and their significance is discussed.