Experimental Measurements of the Eddy Current Signal Due to a Flawed, Conducting Half Space

The eddy current method of nondestructive evaluation involves the induction of eddy currents in a conductive test object by a time-varying field produced by a suitable distribution of impressed currents and the detection of the resultant field. The method is ordinarily used at frequencies sufficiently low to neglect effects due to displacement current; hence a theoretical analysis entails calculating the self-impedance of the coil in the presence of the test object. In practice, one often needs only the change in impedance produced by the test object or by changes in the nominal properties of the test object (e.g., changes in its geometry or position with respect to the test coil or coils, or distributed or localized changes in the resistivity of the test object)

Great Genetic Differentiation among Populations of Meconopsis integrifolia and Its Implication for Plant Speciation in the Qinghai-Tibetan Plateau

The complex tectonic events and climatic oscillations in the Qinghai-Tibetan Plateau (QTP), the largest and highest plateau in the world, are thought to have had great effects on the evolutionary history of the native plants. Of great interest is to investigate plant population genetic divergence in the QTP and its correlation with the geologic and climatic changes. We conducted a range-wide phylogeographical analysis of M. integrifolia based on the chloroplast DNA (cpDNA) trnL-trnF and trnfM-trnS regions, and defined 26 haplotypes that were phylogenetically divided into six clades dated to the late Tertiary. The six clades correspond, respectively, to highly differentiated population groups that do not overlap in geographic distribution, implying that the mountain ranges acting as corridors or barriers greatly affected the evolutionary history of the QTP plants. The older clade of M. integrifolia only occurs in the southwest of the species' range, whereas the distributions of younger clades extend northeastward in the eastern QTP, suggesting that climatic divergence resulting from the uplift of the QTP triggered the initial divergence of M. integrifolia native to the plateau. Also, the nrDNA ITS region was used to clarify the unexpected phylogenetic relationships of cpDNA haplotypes between M. integrifolia and M. betonicifolia. The topological incongruence between the two phylogenies suggests an ancestral hybridization between the two species. Our study indicates that geographic isolation and hybridization are two important mechanisms responsible for the population differentiation and speciation of Meconopsis, a species-rich genus with complex polyploids

Low molecular weight Aβ induces collapse of endoplasmic reticulum

The endoplasmic reticulum (ER) is a dynamic multifunction organelle that is responsible for Ca2+ homeostasis, protein folding, post-translational modification, protein degradation, and transportation of nascent proteins. Disruption of ER architecture might affect the normal physiology of the cell. In yeast, expansion of the ER is observed under unfolded protein response (UPR) and subsequently induces autophagy initiated from the ER. Here, we found that soluble low molecular weight of Aβ disrupted the anchoring between ER and microtubules (MT) and induced collapse of ER. In addition, it decreased the stability of MT. Subsequently, low molecular weight Aβ triggered autophagy and enhanced lysosomal degradation, as shown by electron microscopy and live-cell imaging. Dysfunction of ER can be further proved in postmortem AD brain and transgenic mice bearing APP Swedish mutation by immunohistochemical analysis of calreticulin. Treatment with Taxol, a MT-stabilizing agent, could partially inhibit collapse of the ER and induction of autophagy. The results show that Aβ-induced disruption of MT can affect the architecture of the ER. Collapse/aggregation of the ER may play an important role in Aβ peptide-triggered neurodegenerative processes. © 2009 Elsevier Inc. All rights reserved.link_to_subscribed_fulltex

Opportunity lost? Victorian Labor\u27s enactment of community development 1999-2006

The idea of community development has been evoked by Australian governments over many decades. The expressions of community have differed widely, often as a result of politics rather than informed policy. In 1999, after seven years of radical neo-liberal restructuring in Victoria, the Bracks government found itself unexpectedly elected to power. They faced new challenges such as a diminished public sector, growing social inequality and climate change. The first two terms of Victorian Labor were a seminal period in terms of the role they would invoke for &lsquo;community&rsquo;. Did grass roots participation take a central place, or did rhetoric rule over substance? The evidence points to a government maintaining a neo-liberal trajectory, and thereby losing an opportunity to enable an active citizenry.<br /