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Studied the interrelationships among general fluid intelligence, short-term memory capacity, working memory capacity, and processing speed in 120 young adults and used structural equation modeling to determine the best predictor of general fluid intelligence. Results suggest that working memory capacity, but not short-term memory capacity or processing speed, is a good predictor of general fluid intelligence. (SLD)

Compares explanations of letter-detection errors in the word "the" based on the unitization hypothesis (errors occur because the word is processed as a whole unit, and lower order processes are not completed) to the structural model of reading (errors occur because the syntactic function of the word pulls attention away from this word). Finds consistent support for the unitization hypothesis. (RS)

Well-developed tools from cartography are adapted and used to visualize curved and flat spacetime to further understanding of relativistic effects, while interpretation of these tools is aided through their application to the familiar world map. First spacetime is cut into two-dimensional subspaces that are mapped to the Minkowski or Euclidean plane using map projections. Then, exploiting the cartographic technique of map interruptions, the two-dimensional subspaces are further cut into 'wedges' to minimize the distortion. The mental exercise of sewing the wedges back together aids in visualizing and interpreting the geometry of the spacetime slice. Map distortion indicators alert the reader to the inevitable effects of distortion. This wedge diagram provides a simple yet powerful tool to visualize both flat and curved spacetime geometry. It is more general than the familiar embedding diagram and avoids the pitfall of confusing the space in question with the embedding space. The wedge diagram is applied first to Minkowski spacetime with the cartographers' azimuthal equidistant map projection and, when combined with the wedge technique, provides a simple visualization of the twin paradox. The wedge diagram is then applied to the exterior Schwarzschild spacetime to visualize the physical significance of spacetime curvature. In particular it is shown how gravitational time dilation results from intrinsic curvature of a radial-time slice of spacetime. Then this diagram is applied to the Friedmann–Robertson–Walker (FRW) spacetime revealing how expansion of the Universe results from a qualitatively similar curvature of a radial-time slice, but with the roles of space and time reversed. The analogy between the two spacetimes suggests novel interpretations of the two spacetimes. We interpret the Schwarzschild spacetime as time expanding with increasing distance from the horizon. And we interpret the FRW spacetime as the Universe expanding as the influence of the big bang peters out. [ABSTRACT FROM AUTHOR]

Interchange reconnection has been proposed as a mechanism for the generation of the slow solar wind, and a key contributor to determining its characteristic qualities. In this paper we study the implications of interchange reconnection for the structure of the plasma and field in the heliosphere. We use the Adaptively Refined Magnetohydrodynamic Solver to simulate the coronal magnetic evolution in a coronal topology containing both a pseudostreamer and helmet streamer. We begin with a geometry containing a low-latitude coronal hole that is separated from the main polar coronal hole by a pseudostreamer. We drive the system by imposing rotating flows at the solar surface within and around the low-latitude coronal hole, which leads to a corrugation (at low altitudes) of the separatrix surfaces that separate open from closed magnetic flux. Interchange reconnection is induced both at the null points and separators of the pseudostreamer, and at the global helmet streamer. We demonstrate that a preferential occurrence of interchange reconnection in the "lanes" between our driving cells leads to a filamentary pattern of newly opened flux in the heliosphere. These flux bundles connect to but extend far from the separatrix-web (S-Web) arcs at the source surface. We propose that the pattern of granular and supergranular flows on the photosphere should leave an observable imprint in the heliosphere. [ABSTRACT FROM AUTHOR]

Portable XRF was used to analyse the chemical composition of 52 indigenous Cayo ceramics from excavations and from private collections on Grenada, Lesser Antilles. Initially, a comparative baseline of data representing three different islands (Grenada, St Vincent and Trinidad) was created by analysing with pXRF ceramic material that had previously been analysed both chemically and petrographically. The field data, when compared to the laboratory baseline data, indicated that the majority of the ceramics were made with clay local to Grenada. Four samples were potentially made with clay from another, as yet unidentified, source. [ABSTRACT FROM AUTHOR]

The practice of re-melting glass was well known, certainly from the Roman period onwards. This can be seen not only in ancient literary evidence but also in the archaeological evidence, collections of broken glass have been found in, for example, Pompeii (79 AD) and the Iulia Felix shipwreck (Third century AD). Elevated levels of certain transition metals in archaeological glasses are interpreted as indications of the mixing and/or recycling of different glasses. Assumptions have been made that all glasses could be recycled, but to what extent are these valid? Why does the evidence for the recycling of glass only occur from the Roman period onwards? From the middle of the First millennium BC to the Ninth century AD, natron glass was the predominant glass type in the Mediterranean and Europe, however, plant ash glass was still in use in some areas. To test the effects on the final product of mixing different composition glass types, experimental glasses were made by mixing varying quantities of replica plant ash glass, replica natron glass, and a modern glass. At low temperatures crystalline material formed in the products containing replica plant ash glass. As the plant ash glass content increased, so too did the amount of crystalline material produced. This is due to a combination of the glass compositions and the firing temperature. It appears that natron type glass can be more easily recycled at lower temperatures, although, if a high enough temperature is used then most glass types can be recycled. Early furnace technology, i.e. the vertical heating chamber furnace, may not have been able to achieve these high temperatures, hence the widespread practice of recycling did not begin until after the invention of glassblowing which required a change in the furnace technology to the use of a horizontal heating chamber furnace. [ABSTRACT FROM AUTHOR]

Tumor growth requires angiogenesis, which in turn requires an imbalance in the presence of angiogenic and angiostatic factors. We have shown that the CXC chemokine family, consisting of members that are either angiogenic or angiostatic, is a major determinant of tumor-derived angiogenesis in non-small-cell lung cancer (NSCLC). Intratumor injection of interferon-inducible protein 10 (IP-10, or CXCL10), an angiostatic CXC chemokine, led to reduced tumor growth in a SCID mouse model of NSCLC. In this study, we hypothesized that treatment with CXCL10 would, by restoring the angiostatic balance, improve long-term survival in NSCLC-bearing SCID mice. To test this hypothesis, A549 NSCLC cells were injected in the subcutis of the flank, followed by intratumor injections with CXCL10 continuously (group I), or for ten weeks (group II), or a control group (human serum albumin). Median survival was 169, 130, and 86 days respectively (P<0.0001). We extended these studies to examine the mechanism of prolonged survival in CXCL10-treated mice. CXCL10 treatment inhibited lung metastases, but was dependent upon continued treatment, and was associated with an increased rate of apoptosis in the primary tumor, with no direct effect on the proliferation of the NSCLC cells. Furthermore, the inhibition of lung metastases was due to the angiostatic effect of CXCL10 on the primary tumor, since the rate of apoptosis within lung metastases was unaffected. These data suggest that anti-angiogenic therapy of human lung cancer should be continued indefinitely to realize persistent benefit, and confirms the anti-metastatic capacity of localized angiostatic therapy. [ABSTRACT FROM AUTHOR]