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A phase-field model for the dynamics of a strained solid in contact with its melt is developed. The sharp-interface limit of this model reduces to the continuum equations describing the Asaro–Tiller–Grinfeld instability. In addition, it allows the derivation of generalizations of these equations. The dynamics of extended systems are investigated via the phase-field approach which contains an inherent lower length cutoff, thus avoiding cusp singularities. General initial conditions lead to coarsening. For periodic states, this arises via a series of approximate period doublings, the beginning of which can be demonstrated analytically.

Extracellular concentrations of dopamine in the nucleus accumbens were monitored using microdialysis in ovariectomized female Syrian hamsters hormonally primed with estradiol and progesterone or with a similar regimen of oil injections. Some females in each of these groups had their vaginas occluded with tape, whereas the remaining females' vaginas stayed unoccluded. When exposed to a male, both groups of hormonally primed females showed high levels of lordosis. However, only in the hormone-primed, unoccluded females were there significant elevations of dialysate dopamine during the sexual interactions with the male. There were no significant elevations in dopamine levels in the oil-treated females during interactions with the male. These data suggest that nucleus accumbens dopamine is responsive to stimuli associated with the vaginocervical stimulation received by the female during intromissions by the male. Histological analyses were based on Fluoro-Gold efflux through the probes combined with immunocytochemistry for tyrosine hydroxylase. Probe placements in the rostral accumbens, caudal accumbens, or rostral bed nucleus of the stria terminalis were not distinguishable based on analyses of basal dopamine levels, volume of Fluoro-Gold injection sites, or Fluoro-Gold labeling of midbrain, tyrosine hydroxylase-stained neurons. The number of midbrain neurons containing Fluoro-Gold was positively related to basal dopamine levels, indicating that the amount of dopamine recovered from the nucleus accumbens in microdialysis studies is a function of the number of neurons contributing to the terminal field in the region of the probe.

The problem of reconstructing an unknown light source from measurements of the modulus of the correlation function of the optical field has been investigated experimentally. The practical feasibility of two different techniques is compared. The first method involves the introduction of a reference point source to the side of the unknown source. The second method depends upon the use of filters with exponential response functions in front of the source. Both methods permit the source to be reconstructed from measurements of the modulus alone. The latter technique involves more-sophisticated numerical procedures. Both methods have the advantage that the recovered phase is largely independent of the instrumental transfer function.

LearnENT, an educational app for iOS, was developed to promote a standardized experience otolaryngology in head and neck surgery (OTOHNS) for University of Ottawa medical students. Its development was grounded in pedagogical theory including Laurillard’s design process, Honey and Mumford’s learning styles, and Nielsen’s theory of usability. This paper examines LearnENT's design and development processes as well as the role of mobile apps in medical education. Features of the LearnENT app as they apply to Constructivist learning are also highlighted.

The cancer chemopreventive and cytotoxic properties of 50 extracts derived from Twilight Zone (50–150 m) sponges, gorgonians and associated bacteria, together with 15 extracts from shallow water hard corals, as well as 16 fractions derived from the methanol solubles of the Twilight Zone sponge Suberea sp, were assessed in a series of bioassays. These assays included: Induction of quinone reductase (QR), inhibition of TNF-α activated nuclear factor kappa B (NFκB), inhibition of aromatase, interaction with retinoid X receptor (RXR), inhibition of nitric oxide (NO) synthase, inhibition 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH), and inhibition of HL-60 and MCF-7 cell proliferation. The results of these assays showed that at least 10 extracts and five fractions inhibited NFκB by greater than 60%, two extracts and two fractions inhibited DPPH by more than 50%, nine extracts and two fractions affected the survival of HL-60 cells, no extracts or fractions affected RXR, three extracts and six fractions affected quinone reductase (QR), three extracts and 12 fractions significantly inhibited aromatase, four extracts and five fractions inhibited nitric oxide synthase, and one extract and no fractions inhibited the growth of MCF-7 cells by more than 95%. These data revealed the tested samples to have many and varied activities, making them, as shown with the extract of the Suberea species, useful starting points for further fractionation and purification. Moreover, the large number of samples demonstrating activity in only one or sometimes two assays accentuates the potential of the Twilight Zone, as a largely unexplored habitat, for the discovery of selectively bioactive compounds. The overall high hit rate in many of the employed assays is considered to be a significant finding in terms of “normal” hit rates associated with similar samples from shallower depths.

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