Diagrams of stability of circumbinary planetary systems

The stability diagrams in the “pericentric distance — eccentricity” plane of initial data are built and analyzed for Kepler-38, Kepler-47, and Kepler-64 (PH1). This completes a survey of stability of the known up to now circumbinary planetary systems, initiated by Popova & Shevchenko (2013), where the analysis was performed for Kepler-16, 34, and 35. In the diagrams, the planets appear to be “embedded” in the fractal chaos border; however, I make an attempt to measure the “distance” to the chaos border in a physically consistent way. The obtained distances are compared to those given by the widely used numerical-experimental criterion by Holman & Wiegert (1999), who employed smooth polynomial approximations to describe the border. I identify the resonance cells, hosting the planets.

THE COMPETENCE-BASED FOCUSED FORMS OF ESTIMATION OF PROFESSIONAL FOREIGN-LANGUAGE COMMUNICATIVE COMPETENCE (CRITERIA ESTIMATION)

The article contains a description of an experimental criterion referenced assessment marking schemes design based on the theory of the socio-cultural approach to cognitive development (Zimnaya I.A.). The article envisages the progress in ESP writing and speaking skills as a part of cognitive development and suggests a cognitive development oriented progression of communication tasks necessary to reach the required ESP learning outcomes - communicative competence in ESP. It also contains a pedagogical strategy of developing criteria-referenced descriptors of performance assessment which serve as guidelines for teachers as well as a strategy of developing checking lists for students. The article provides some significant insights into the effect of criteria- referenced assessment on teacher and student development.

A Whistling Criterion for Two Orifices in Series

Whistling phenomena in pipe power plants have been observed in the past years. It occurs at pressure drop devices where vortex shedding is established. It generates high noise levels and excessive vibrations. Aure´gan and Starobinsky [1] have developed an experimental criterion to predict whistling frequencies of pressure drop devices submitted to plane propagating pressure waves. This criterion estimates the net acoustic power, an acoustic exergy generation indicating that the device behaves as an acoustic amplifier. The corresponding frequencies are potential whistling frequencies. The application of the criterion only requires the determination of the scattering matrix of the device. In previous works, this criterion was applied to different single hole orifices. The purpose of the present study is to apply the criterion to two orifices in series and to verify that the behavior of this system can be predicted from the scattering matrix of each individual orifice and of the straight pipe in-between. Measurements are done on an air test rig with an inner diameter of 3 cm, a Mach number of 2.6 × 10−2 and a Reynolds number of 104. Different distances between orifices are characterized. The study of the influence of the second orifice on the whistling criterion shows an enhancement of the whistling potential and a shift of the main potential whistling frequency. A fair agreement is found between experimental and predicted results. Characterization of orifices in series is then possible from the coefficients of the scattering matrix of one orifice and an appropriate condition on the distance between the orifices.

Differential Inhibition of Ca2+ Channels by α2-Adrenoceptors in Three Functional Subclasses of Rat Sympathetic Neurons

A comparison of identified sympathetic neurons in the isolated intact superior cervical ganglion revealed that secretomotor, pilomotor, and vasoconstrictor cells differ in their action potential mechanisms and in their postsynaptic α2-adrenergic responses to 10 μM norepinephrine (NE). In normal saline, the half-width of the spike afterhyperpolarization (AHP) in secretomotor neurons (103.5 ± 6.2 ms) was twofold that recorded in vasoconstrictor neurons (47.7 ± 2.9 ms) and 1.5-fold that in pilomotor neurons (71.4 ± 10.3 ms). Bath-applied NE reversibly inhibited the action potential repolarization shoulder, AHP amplitude, and AHP duration in secretomotor and pilomotor neurons to a similar extent, but had no effect on vasoconstrictor neurons. The insensitivity of vasomotor neurons to NE was not an artifact produced by microelectrode recording because all three cell groups were similar in terms of resting potential and input resistance. Moreover, NE insensitivity was not a natural consequence of briefer AHP duration in vasoconstrictor cells. Adding 10 mM TEA+ caused marked accentuation of the shoulder and AHP duration in vasoconstrictor neurons and comparable changes in the other two cell types, but did not unmask any sign of NE sensitivity in the vasoconstrictors. However, the spike shoulder and AHP in vasoconstrictors were Cd2+ sensitive, blocked by ω-conotoxin, an N-type calcium channel antagonist, and inhibited by oxotremorine-M, a muscarinic receptor agonist. These data show that NE can differentially modulate functional subsets of mammalian sympathetic neurons and that NE insensitivity can serve as a practical experimental criterion for identification of vasomotor neurons in the isolated ganglion.