Combination of high-resolution cone beam computed tomography and metal artefact reduction software: a new image fusion technique for evaluating intracranial stent apposition after aneurysm treatment.

We introduce a new imaging technique to improve visualisation of stent apposition after endovascular treatment of brain aneurysms employing high-resolution cone beam CT and three-dimensional digital subtraction angiography. After performing a stent-assisted coil embolisation of brain aneurysm, the image datasets were processed with a metal artefact reduction software followed by the automated image fusion programmes. Two patients who underwent aneurysm coiling using a Neuroform stent were evaluated. The reconstructed 3D images showed a detailed structure of the stent struts and identified malappositions of the deployed stents. Case 1 showed good apposition on the outer curvature side of the carotid siphon, while the inner curvature side showed prominent malapposition. Case 2, with multiple aneurysms, showed good apposition on both outer and inner curvature sides, although inward prolapse of the struts was observed. This new imaging technique may help evaluate stent apposition after the endovascular aneurysm treatment

Apposition

The term Apposition has given rise to many disputes over its range of occurrence and its affinity with the Epithet. This article is an attempt to detect theoretical and logical ambiguities concerning the Apposition in the analyses of Armenian and French syntax. After a brief presentation of “contradictions”, the author tries to explore the internal logic which caused them. Then, the problem is reviewed again in the light of the cognitive grammar

Butterfly Optics Exceed the Theoretical Limits of Conventional Apposition Eyes

Optical experiments on butterfly compound eyes show that they have angular sensitivities narrower than expected from conventional apposition eyes. This superior performance is explained by a theoretical model where the cone stalk is considered as a modecoupling device. In this model the Airy diffraction pattern of the corneal facet excites a combination of the two waveguide modes LP01 and LP02. When the two modes propagate through the cone stalk the power of LP02 is transferred to LP01 alone which is supported by the rhabdom. This mechanism produces a higher on-axis sensitivity and a narrower angular sensitivity than conventional apposition optics. Several predictions of the model were confirmed experimentally.

Nominal juxtaposition in Australian languages: An LFG analysis

It is well known that Australian languages make heavy use of nominal juxtaposition in a wide variety of functions, but there is little discussion in the theoretical literature of how such juxtapositions should be analysed. We discuss a range of data from Australian languages illustrating how multiple nominals share a single grammatical function within the clause. We argue that such constructions should be treated syntactically as set-valued grammatical functions in Lexical-Functional Grammar (LFG). Sets as values for functions are well-established in LFG and are used in the representation of adjuncts, and also in the representation of coordination. In many Australian languages, coordination is expressed asyndetically, that is, by nominal juxtaposition with no overt coordinator at all. We argue that the syntactic similarity of all juxtaposed constructions (ranging from coordination through a number of more appositional relations) motivates an analysis in which they are treated similarly in the syntax, but suitably distinguished in the semantics. We show how this can be achieved within LFG, providing a unified treatment of the syntax of juxtaposition in Australian languages and showing how the interface to the semantics can be quite straightforwardly defined in the modular LFG approach. Copyright © Cambridge University Press 2009

Inhibition of gap junction and adherens junction assembly by connexin and A-CAM antibodies

We examined the roles of the extracellular domains of a gap junction protein and a cell adhesion molecule in gap junction and adherens junction formation by altering cell interactions with antibody Fab fragments. Using immunoblotting and immunocytochemistry we demonstrated that Novikoff cells contained the gap junction protein, connexin43 (Cx43), and the cell adhesion molecule, A-CAM (N-cadherin). Cells were dissociated in EDTA, allowed to recover, and reaggregated for 60 min in media containing Fab fragments prepared from a number of antibodies. We observed no cell-cell dye transfer 4 min after microinjection in 90% of the cell pairs treated with Fab fragments of antibodies for the first or second extracellular domain of Cx43, the second extracellular domain of connexin32 (Cx32) or A-CAM. Cell-cell dye transfer was detected within 30 s in cell pairs treated with control Fab fragments (pre-immune serum, antibodies to the rat major histocompatibility complex or the amino or carboxyl termii of Cx43). We observed no gap junctions by freeze-fracture EM and no adherens junctions by thin section EM between cells treated with the Fab fragments that blocked cell-cell dye transfer. Gap junctions were found on approximately 50% of the cells in control samples using freeze-fracture EM. We demonstrated with reaggregated Novikoff cells that: (a) functional interactions of the extracellular domains of the connexins were necessary for the formation of gap junction channels; (b) cell interactions mediated by A-CAM were required for gap junction assembly; and (c) Fab fragments of antibodies for A-CAM or connexin extracellular domains blocked adherens junction formation

On the interpretation of wh-clauses in exclamative environments

In this paper, a class of sentences in German is discussed that are often called whexclamatives. […] So called wh-exclamatives can be roughly characterized as wh-clauses that are embedded under exclamative predicates like erstaunt sein/to be amazed at [...] or that are used as the basis for an exclamation [...]. One can ask if wh-exclamatives are a clause-type of their own, in particular, whether they are different from wh-clauses in question environments, that is under question predicates like to ask or to wonder or used as questions. It is often assumed that wh-clauses in exclamative contexts, both embedded and unembedded, are indeed different from wh-clauses in interrogative or question environments [...], at least regarding their semantical type, see for example Elliot (1971, 1974), Grimshaw (1979, 1981), Zaefferer (1983, 1984), Altmann (1 987, 1993). […] I assume with Grimshaw (1979) that so called wh-exclamatives and wh-interrogatives are alike with respect to their syntactical properties. In addition, I think that they are also alike semantically. So, what I like to do here is to evaluate the following hypothesis: So-called wh-exclamatives are of the same semantical type as wh-interrogatives

Maxillary expansion in an animal model with light, continuous force

Objectives: Maxillary constriction is routinely addressed with rapid maxillary expansion (RME). However, the heavy forces delivered by most RME appliances to expand the palate may lead to deleterious effects on the teeth and supporting tissues. The objective of this study was to explore a more physiologic maxillary expansion with light continuous force. Materials and Methods: Twenty 6-week-old Sprague-Dawley rats were equally divided into experimental (EXPT) and control (CTRL) groups. A custom-fabricated archwire expansion appliance made from 0.014-inch copper-nickel-titanium wire was activated 5 mm and bonded to the maxillary molar segments of animals in the EXPT group for 21 days. The force applied to each maxillary segment was 5 cN. Microfocus x-ray computed tomography and histological analyses were used to compare the tooth movement and bone morphology in the midpalatal suture and buccal aspect of the alveolar process between the EXPT and CTRL groups. Descriptive statistics (mean ± standard error of the mean) and nonparametric statistical tests were used to compare the outcomes across groups. Results: Compared to the CTRL group, there was a statistically significant increase in buccal tooth movement and expansion of the midpalatal suture in the EXPT group. There was no difference in the bone morphologic parameters between groups. The mineral apposition rate was increased on the buccal surface of the alveolar process in the EXPT group. Conclusions: Application of light, continuous force resulted in maxillary osseous expansion due to bilateral sutural apposition and buccal drift of the alveolar processes. This animal experiment provides a more physiologic basis for maxillary expansion