Comparative genomic hybridization analysis of craniopharyngiomas

Object. Craniopharyngioma is the most common childhood brain tumor and is thought to arise from embryonic remnants of the Rathke pouch. Some craniopharyngiomas are monoclonal in origin and hence presumably harbor somatic genetic alterations, although the precise molecular mechanisms involved in craniopharyngioma development are unknown. The goal of this study was to identify genetic alterations in craniopharyngiomas. Methods. To gain insight into the molecular mechanisms involved in development of these tumors, the authors analyzed nine adamantinomatous craniopharyngiomas by using comparative genomic hybridization. Six tumors (67%) displayed at least one genomic alteration, and three had six or more alterations. Only two tumors displayed a decrease in DNA copy number, and in all others an increase in DNA copy number was noted. Conclusions. The authors conclude that a subset of craniopharyngiomas consists of monoclonal tumors arising from activation of oncogenes located at specific chromosomal loci.

Variation in spoken discourse in and beyond the english foreign language classroom : a comparative study

This study is concerned with one of the most interesting and the least well-researched areas in contemporary research on classroom interaction: that of the discourse variability exhibited by participants. It investigates the way in which the language of native speakers (NSs) as well as that of non-native speakers (NNSs) may vary according to the circumstances under which it is produced. The study, therefore, attempts to characterise the performance of both NSs and NNSs (with particular emphasis placed on the latter) in various types of interaction in and beyond the EFL classroom. These are: Formal Interview (FI), Formal Classroom Interaction (FCI), Informal Classroom Interaction (ICI), Informal Classroom Discussion (ICD), and Informal Conversation (IC). The corpus of the study consisted of four NSs and fifteen NNSs. Both a video and a tape recording was made for each type of interaction, with the exception of the IC which was only audio-recorded so as not to inhibit the natural use of language. Each lasted for 35 minutes. The findings of the study mark clearly the distinction between the `artificiality' of classroom interaction and the `naturalness' or `authenticity' of non-classroom discourse. Amongst the most interesting findings are the following: Unlike both FCI and ICI, in the FI, ICD, and IC, the language of NNSs was characterised by: greater quantity of oral output, a wider range of errors, the use of natural discourse strategies such as holding the floor and self-correction, and a greater number of initiations in both ICD and IC. It is suggested that if `natural' or `authentic' discourse is to be promoted, the incorporation of FI, ICD, and IC into the EFL classroom activities is much needed. The study differs from most studies on classroom interaction in that it attempts to relate work in the EFL classroom to the `real' world as its prime objective.

Radical or not so radical? Tactical variation in core policy formation by the Front National

Starting from a number of general tenets about radical political parties, this article examines the Front National (FN) in relation to its core policy issue of immigration. To what extent has FN immigration policy been defined from the outset by its radicalism? Has that radicalism been constant or variable over time? And how far can a reciprocal influence be detected between the FN and the center Right in immigration policy formulation? Focusing on election campaigns, manifestos, and key moments in the FN's evolution, the article assesses how the party has tailored its radicalism to contextual factors and tactical considerations. It reveals an FN less bound to a fixed policy and more ready to seek accommodation (with circumstance, public opinion, or the center Right) than is generally acknowledged. Conversely, it also assesses how the FN's mobilization of strong support on the immigration issue has had radicalizing effects on the center Right. The article concludes by considering whether the change of leadership in January 2011 might confine the FN to the radical Right or see it adopt a more center-oriented course.

Integrated Dimensional Variation Management in the Digital Factory

This paper describes how dimensional variation management could be integrated throughout design, manufacture and verification, to improve quality while reducing cycle times and manufacturing cost in the Digital Factory environment. Initially variation analysis is used to optimize tolerances during product and tooling design and also results in the creation of a simplified representation of product key characteristics. This simplified representation can then be used to carry out measurability analysis and process simulation. The link established between the variation analysis model and measurement processes can subsequently be used throughout the production process to automatically update the variation analysis model in real time with measurement data. This ‘live’ simulation of variation during manufacture will allow early detection of quality issues and facilitate autonomous measurement assisted processes such as predictive shimming. A study is described showing how these principles can be demonstrated using commercially available software combined with a number of prototype applications operating as discrete modules. The commercially available modules include Catia/Delmia for product and process design, 3DCS for variation analysis and Spatial Analyzer for measurement simulation. Prototype modules are used to carry out measurability analysis and instrument selection. Realizing the full potential of Metrology in the Digital Factory will require that these modules are integrated and software architecture to facilitate this is described. Crucially this integration must facilitate the use of realtime metrology data describing the emerging assembly to update the digital model.

Dialect variation

Relatively little research on dialect variation has been based on corpora of naturally occurring language. Instead, dialect variation has been studied based primarily on language elicited through questionnaires and interviews. Eliciting dialect data has several advantages, including allowing for dialectologists to select individual informants, control the communicative situation in which language is collected, elicit rare forms directly, and make high-quality audio recordings. Although far less common, a corpus-based approach to data collection also has several advantages, including allowing for dialectologists to collect large amounts of data from a large number of informants, observe dialect variation across a range of communicative situations, and analyze quantitative linguistic variation in large samples of natural language. Although both approaches allow for dialect variation to be observed, they provide different perspectives on language variation and change. The corpus- based approach to dialectology has therefore produced a number of new findings, many of which challenge traditional assumptions about the nature of dialect variation. Most important, this research has shown that dialect variation involves a wider range of linguistic variables and exists across a wider range of language varieties than has previously been assumed. The goal of this chapter is to introduce this emerging approach to dialectology. The first part of this chapter reviews the growing body of research that analyzes dialect variation in corpora, including research on variation across nations, regions, genders, ages, and classes, in both speech and writing, and from both a synchronic and diachronic perspective, with a focus on dialect variation in the English language. Although collections of language data elicited through interviews and questionnaires are now commonly referred to as corpora in sociolinguistics and dialectology (e.g. see Bauer 2002; Tagliamonte 2006; Kretzschmar et al. 2006; D'Arcy 2011), this review focuses on corpora of naturally occurring texts and discourse. The second part of this chapter presents the results of an analysis of variation in not contraction across region, gender, and time in a corpus of American English letters to the editor in order to exemplify a corpus-based approach to dialectology.

Regional variation in written American English

The first study of its kind, Regional Variation in Written American English takes a corpus-based approach to map over a hundred grammatical alternation variables across the United States. A multivariate spatial analysis of these maps shows that grammatical alternation variables follow a relatively small number of common regional patterns in American English, which can be explained based on both linguistic and extra-linguistic factors. Based on this rigorous analysis of extensive data, Grieve identifies five primary modern American dialect regions, demonstrating that regional variation is far more pervasive and complex in natural language than is generally assumed. The wealth of maps and data and the groundbreaking implications of this volume make it essential reading for students and researchers in linguistics, English language, geography, computer science, sociology and communication studies.