The pseudo McMillan degree of implicit transfer functions of RLC networks

We study the structure of a given RLC network without sources. Since the McMillan degree of the implicit transfer function is not a suitable measure of complexity of the network, we introduce the pseudo McMillan degree to overcome these shortcomings.Using modified nodal analysis models, which are linked directly to the natural network topology, we shaw that the pseudo-McMillan degree equals the sum of the number of capacitors and inductors minus the number of fundamental loops of capacitors and fundamental cutsets of inductors; this is the number of independent dynamic elements in the network. Exploiting this representation we derive a minimal realization of the given RLC network, that is one where the number of independent differential equations equals the pseudo McMillan degree

p27(Kip1 )is expressed in proliferating cells in its form phosphorylated on threonine 187

BACKGROUND: G1/S cell cycle progression requires p27(Kip1 )(p27) proteolysis, which is triggered by its phosphorylation on threonine (Thr) 187. Since its levels are abundant in quiescent and scarce in cycling cells, p27 is an approved marker for quiescent cells, extensively used in histopathology and cancer research. METHODS: However here we showed that by using a specific phosphorylation site (pThr187) antibody, p27 is detectable also in proliferative compartments of normal, dysplastic and neoplastic tissues. RESULTS: In fact, whereas un-phosphorylated p27 and MIB-1 showed a significant inverse correlation (Spearman R = -0.55; p < 0,001), pThr187-p27 was positively and significantly correlated with MIB-1 expression (Spearman R = 0.88; p < 0,001). Thus proliferating cells only stain for pThr187-p27, whereas they are un-reactive with the regular p27 antibodies. However increasing the sensitivity of the immunocytochemistry (ICH) by the use of an ultra sensitive detection system based on tiramide signal amplification, simultaneous expression and colocalisation of both forms of p27 was shown in proliferating compartments nuclei by double immunofluorescence and laser scanning confocal microscopy studies. CONCLUSION: Overall, our data suggest that p27 expression also occurs in proliferating cells compartments and the combined use of both regular and phospho- p27 antibodies is suggested

Formulaic Language in Native and Second Language Speakers: Psycholinguistics, Corpus Linguistics, and TESOL

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/89473/1/j.1545-7249.2008.tb00137.x.pd

A thermogravimetric study of the oxidative growth of Al2O3/Al alloy composites

The oxidation of liquid Al–Mg–Si alloys at 900–1400 °C was studied by thermogravimetric analysis (TGA). The development of a semi-protective surface layer of MgO/MgAl2O4 allows the continuous formation of an Al2O3-matrix composite containing an interpenetrating network of metal microchannels at 1000–1350 °C. An initial incubation period precedes bulk oxidation, wherein Al2O3 grows from a near-surface alloy layer by reaction of oxygen supplied by the dissolution of the surface oxides and Al supplied from a bulk alloy reservoir through the microchannel network. The typical oxidation rate during bulk growth displays an initial acceleration followed by a parabolic deceleration in a regime apparently limited by Al transport to the near-surface layer. Both regimes may be influenced by the Si content in this layer, which rises due to preferential Al and Mg oxidation. The growth rates increase with temperature to a maximum at ~1300 °C, with a nominal activation energy of 270 kJ/mole for an Al-2.85 wt. % Mg-5.4 wt. % Si alloy in O2 at furnace temperatures of 1000–1300 °C. An oscillatory rate regime observed at 1000–1075 °C resulted in a banded structure of varying Al2O3-to-metal volume fraction