Szabolcs Tóth

Egg activation in mammals is caused by cytosolic Ca(2+) oscillations that are essential for development. However, despite increasing knowledge about signal transduction mechanisms, the functional linkage between frequency number, amplitude and duration of the Ca(2+) signal and the kinetics of pronucleus formation has not yet been defined. While a wide range of Ca(2+) signal parameters are efficient in causing egg activation, the basic rules governing how the egg integrates these signalling events are not yet clear. Thus, in the perspective of better understanding how the egg processes Ca(2+) signalling events, the objective of this study was to determine experimentally whether the efficiency of egg activation and the subsequent early developmental stages rely on Ca(2+) signalling summation. Non-fertilized, but freshly ovulated mouse eggs, were subjected to a series of repetitive Ca(2+) influxes of various patterns modulated by a non-invasive membrane electropermeabilization method. Using a combination of two suboptimal treatments we have shown that mouse eggs can sum up the effects caused by various patterns of intracellular Ca(2+) concentrations transient during the period of egg activation. In addition, overloading the intracellular milieu by repetitive Ca(2+) influxes did not seem to inhibit the process of activation. The kinetics of pronuclear formation among a population of eggs treated in the same conditions became accelerated when the total dose of Ca(2+) signal 'experienced' by the eggs was increased. The results suggested that summation of the biological effects of all Ca(2+) signals constitutes an important mode of Ca(2+) signal integration.

Ground testing campaign conducted on the FLEXOP demonstrator aircraft is presented in this paper. The conducted tests are grouped in structural, flight system and integration tests. Along with the description of the test setup and test execution, the main findings and conclusions are also given. The structural tests comprise the static, ground vibration and the airworthiness test. The static and the ground vibration tests were used for structural characterisation of the manufactured wings and airframe as a whole. Assessment and calibration of the Fibre Brag strain sensing system for wing shape and load reconstruction is also presented within this context. The airworthiness test is used to demonstrate the structural integrity of the manufactured wings under specified limit loads. Within the context of the flight system tests, the main components of the on-board autopilot hardware-software system are briefly introduced including the signal data flow from the RC transmitter to the aircraft controls, the functionality of the baseline autopilot software and the communication with the ground station. All of these components are integrated into the hardware-in-the-loop environment, which is also briefly introduced along with the servo motor identification and the hardware delay measurements. The measured hardware delay was considered in the design of the baseline and flutter controllers. The flutter controllers were tested together with the baseline controller in the software-in-the-loop environment. System integration tests are presented last. In this context the airbrake, the engine, the compatibility of electronic components, the range and the taxi tests are presented.