452 research outputs found
Tensions entre politique du changement et stabilité: une dynamique nécessaire pour l'innovation dans les centres de langues universitaires
The evaluation of a university language center, to establish the extent to which it is an effective and leading-edge institution, must focus on five major factors: The quality of its language learning/teaching, its teachers' pre-service and in-service training, its treatment of students, its premises and equipment, and its management. Any decision to innovate to improve quality in one of these areas will always impact on the other areas. Managing change successfully in a university language center thus requires analysis of the tensions and impacts that innovation in one area may generate for the entire structure. To illustrate the questions involved, we will use case studies to examine the implications for all the various actors of a university language center of the establishment of online placement testing and online registration within a center. Using new technology in this innovative manner affects a number of areas that develop tensions between each other. The set of tensions which arises is a dynamic factor required for the development of language centers which wish to remain competitive, but it requires proactive measures which anticipate the changes to be made, while still maintaining the highest standards at all level
Experimental Investigation of the Flow Dynamics in Models of Patient-Specific Aneurysms
This work investigates the complex flow dynamics in patient-specific compliant models of Abdominal Aortic Aneurysms (AAA) using time-resolved Particle Image Velocimetry (PIV). Scans of multiple planes were performed on three different models: a healthy aorta, a 4-cm saccular AAA, and a 7-cm fusiform AAA. We discuss the differences in flow patterns in patient-specific models compared to idealized models from previous work. We note that the curvature of the aorta upstream from the aneurysm, specific placement of the iliac arteries, and the overall symmetry of the aneurysm have important effects on flow structures, such as increasing transient effects, vortex formation, and wall impingement. Viscous energy dissipation rate (VEDr) was also evaluated as it has been previously identified as a potentially good metric to assess the severity of some vascular diseases.
Finally, a modal analysis was performed on the velocity fields using Proper Orthogonal Decomposition (POD). The main modes obtained were inspected to identify the dominant structures, and the distribution of energy between the modes (Shannon entropy), and to create a reduced-order model of the flow. The results show that Shannon entropy was significantly different between the three models, suggesting that it can be a promising clinical parameter to evaluate the severity of AAAs
Mise en jeux de la grammaire
Longtemps considérée comme une pièce maitresse de l’enseignement/apprentissage du français langue étrangère, il semblerait que, de nos jours, la grammaire ait du
jeu. C’est justement la problématique de l’articulation entre jeu et grammaire que nous traitons dans cette étude. A travers l’analyse qualitative et quantitative de 135 questionnaires, nous avons étudié les représentations des apprenants et, dans
le cadre d’une recherche-action, nous avons examiné les rapports qu’entretiennent grammaire et jeu, en classe. Nous avons également mis en avant des pratiques pédagogiques dont l’objectif est de faire jouer avec profit les apprenants à la
grammaire, en classe de langue
Possible doublet mechanism for a regular component of parity violation in neutron scattering
A nucleus with octupole deformation of the mean field reveals rotational
doublets with the same angular momentum and opposite parity. Mediated by the
Coriolis-type interaction, the doublet structure leads to a strong regular
component in the parity violation caused by weak interaction. This can explain
sign correlations observed in polarized neutron scattering by Th.Comment: 10 pages, revtex, no figure
Colorectal neuroendocrine carcinomas and adenocarcinomas share oncogenic pathways. A clinico-pathologic study of 12 cases
OBJECTIVE:
Neuroendocrine carcinomas (NECs) are rare neoplasms with an increasing incidence. Oncogenetic pathways of colorectal NEC are still poorly understood, and no treatment standards are available for these rare tumors.
METHODS:
We analyzed retrospectively the clinical records and histology of 12 patients with colorectal NEC. KRAS and BRAF mutations were investigated after the dissection of exoendocrine and neuroendocrine components. ALK alterations and EML4-ALK transcripts were detected by in-situ hybridization and determination of fusion transcripts, respectively.
RESULTS:
At the time of diagnosis, the mean age of the patients was 60 years (40-79) and 10 patients had synchronous metastases. A transient response occurred in two patients and one patient treated with cisplatin-etoposide or fluoropyrimidine-oxaliplatin, respectively. Tumor progression-related death occurred in 11 of 12 patients. Ten tumors contained an exocrine component, accounting for 5-70% of the tumor, and the other two contained an amphicrine component. BRAF/KRAS mutations were found in six of 10 tumors, corresponding to BRAF(V600E) (n=2) or KRAS(G12D) (n=2), KRAS(G12V) or KRAS(G13D). DNA was obtained from both exocrine and endocrine components in seven cases, and the BRAF/KRAS status was identical in all cases. Split of the ALK locus was detected in a minority of tumor cells in two of eight cases, but EML4-ALK transcripts were absent.
CONCLUSION:
The association of an exocrine component in all cases and the similar profile of BRAF/KRAS mutations indicate that colorectal NEC may correspond to a high-grade transformation of colorectal carcinoma. New chemotherapy regimens using targeted therapies should be assessed in these tumors
Fission barriers and asymmetric ground states in the relativistic mean field theory
The symmetric and asymmetric fission path for 240Pu, 232Th, and 226Ra is
investigated within the relativistic mean field model. Standard
parametrizations which are well fitted to nuclear ground state properties are
found to deliver reasonable qualitative and quantitative features of fission,
comparable to similar nonrelativstic calculations. Furthermore, stable octupole
deformations in the ground states of Radium isotopes are investigated. They are
found in a series of isotopes, qualitatively in agreement with nonrelativistic
models. But the quantitative details differ amongst the models and between the
various relativsitic parametrizations.Comment: 30 pages RevTeX, 7 tables, 12 low resolution Gif figures (high
resolution PostScript versions are available at
http://www.th.physik.uni-frankfurt.de/~bender/nucl_struct_publications.html
or at ftp://th.physik.uni-frankfurt.de/pub/bender
Corrigendum: Frequency-Specific Fractal Analysis of Postural Control Accounts for Control Strategies
International audienc
Nearby Doorways, Parity Doublets and Parity Mixing in Compound Nuclear States
We discuss the implications of a doorway state model for parity mixing in
compound nuclear states. We argue that in order to explain the tendency of
parity violating asymmetries measured in Th to have a common sign,
doorways that contribute to parity mixing must be found in the same energy
neighbourhood of the measured resonance. The mechanism of parity mixing in this
case of nearby doorways is closely related to the intermediate structure
observed in nuclear reactions in which compound states are excited. We note
that in the region of interest (Th) nuclei exhibit octupole
deformations which leads to the existence of nearby parity doublets. These
parity doublets are then used as doorways in a model for parity mixing. The
contribution of such mechanism is estimated in a simple model.Comment: 11 pages, REVTE
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