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Dieser Artikel untersucht die Hauptergebnissse der empirischen Forschung, die in Frankreich in den letzten 15 Jahren durchgeführt worden sind und die sich auf technische Graphen beziehen. Diese kürzlich veröffentlichten Arbeiten berichten über die parallele Entwicklung der Unterrichtsmethoden und -inhalte, die sich aus der Einführung neuer technischer Graphen ergeben, sowie über die Art und die Ursachen der Schwierigkeiten, auf die die Lernenden (Schüler, Studenten oder Erwachsene in Fortbildungskursen) bei Aufgaben, die den Einsatz dieser Graphen erfordern, stossen. Die Forschungsarbeiten behandeln die Problematiken, die im Zusammenhang mit Darstellungsweisen mechanischer Systeme auftreten, sowie bei Konzipierungsprozessen industrieller Produkte und bei Automatismen., This article takes a look at the principle results of experimental research carried out in France over the last 15 years as pertains to technical graphics. The research work considered the simultaneous changes that occurred in teaching methods and content as a result of the recent implementation of new technical graphics as well as the nature and causes of learner difficulties (i. e. pupils, students and adults in continuing education) during task work requiring the use of the graphics concerned. It studied the issues resulting from learner understanding of mechanical systems, the process of industrial product development as well as automatisms., Cet article passe en revue les principaux résultats de recherches empiriques menées en France ces quinze dernières années et relatives aux graphismes techniques. Ces travaux rendent compte à la fois de l’évolution parallèle des méthodes et des contenus d’enseignement résultant de l’introduction récente dans l’enseignement technologique de nouveaux graphismes techniques, et de la nature et des causes des difficultés qu’éprouvent les apprenants (élèves, étudiants ou adultes en formation) lors de tâches mettant en œuvre ce type de graphisme. Ces recherches traitent de problématiques liées aux modes de représentation des systèmes mécaniques, aux processus de conception de produits industriels et aux automatismes., Este artículo pasa en revista los principales resultados de investigaciones empíricas llevadas a cabo en Francia estos últimos 15 años y relativas a los grafismos técnicos. Estos trabajos dan cuenta, a la vez de la evolución paralela de los métodos y de los contenidos de enseñanza que resultan de la introducción reciente, en la enseñanza tecnológica, de nuevos grafismos técnicos y también, de la naturaleza y de las causas de la dificultades que experimentan los alumnos, los estudiantes o los adultos en formación, durante las tareas que ponen en práctica este tipo de grafismo. Estas investigaciones tratan de problemáticas vinculadas con los modos de representación de los sistemas mecánicos, con los procesos de concepción de productos industriales y con los automatismos., Hamon Christian. Graphismes techniques : tâches, nature et causes des difficultés des apprenants. In: Aster, n°48, 2009. Mesure et instrumentation dans l'enseignement scientifique. pp. 39-61.

SummaryBackgroundMinimizing delays to coronary reperfusion is critical in the management of acute myocardial infarction (AMI).AimsTo determine delays in in-hospital management and factors associated with delays of over 45min.MethodsWe analysed data from the Observatoire Régional Breton sur l’Infarctus, a registry of AMI patients admitted within 24h of symptom onset (July 2007 to December 2008) to an interventional cardiology centre in Brittany. Prehospital delay was defined as time between first responder arrival at the patient and patient arrival at an interventional cardiovascular centre. In-hospital delay was defined as time between admission to the interventional cardiovascular centre and first balloon inflation. Patients were grouped according to duration of in-hospital delay (>45 vs ≤45min). Predictors of short in-hospital delay (≤45min) were examined by logistic regression analysis.ResultsThe analysis included 560 patients (mean age 60.7±13 years; 443 men). Median delay between symptom onset and call for medical assistance was 50min (mean 115±180). Two-thirds (n=371) of patients were admitted to hospital during working hours (08:00–20:00h); 383 (68%) patients were managed by emergency medical services before admission. In-hospital delay was less than or equal to 45min for 296 (53%) patients. The mean overall (pre- and in-hospital) delay was 140 (median 109) min. Direct admission to a catheterization laboratory and admission during working hours were independently correlated with short in-hospital delay (odds ratios 20.8 [p

A novel MS/MS-based analysis strategy using isotopomer labels, referred to as "tandem mass tags" (TMTs), for the accurate quantification of peptides and proteins is described. The new tags are designed to ensure that identical peptides labeled with different TMTs exactly comigrate in all separations. The tags require novel methods of quantification analysis using tandem mass spectrometry. The new tags and analysis methods allow peptides from different samples to be identified by their relative abundance with greater ease and accuracy than other methods. The new TMTs permit simultaneous determination of both the identity and relative abundances of peptide pairs using a collision induced dissociation (CID)-based analysis method. Relative abundance measurements made in the MS/MS mode using the new tags are accurate and sensitive. Compared to MS-mode measurements, a very high signal-to-noise ratio is achieved with MS/MS based detection. The new tags should be applicable to a wide variety of peptide isolation methods.

A process of speech synthesis from diphones stored in a dictionary as waveforms, for text-to-speech conversion, comprises supplying a sequence of phoneme codes and respective prosodic information, and, for each phoneme, analyzing and synthesizing each phoneme, and then concatenating the synthesized phonemes. For each phoneme, two diphones are selected among the stored diphones and the presence of voicing is determined. For voiced phonemes, the respective waveforms of the two diphones constituting the phoneme are filtered by a window which is centered on a point of the selected waveform representative of the beginning of a pulse response of vocal cords to excitation thereof. The window has a width substantially equal to twice the greater of the original fundamental period and the fundamental synthesis period and has an amplitude progressively decreasing from the center of the window. The signals resulting from the filtering and obtained for each diphone are time shifted so as to be spaced apart by a time equal to the fundamental synthesis period. Synthesis is achieved by adding the displaced overlapping signals.

The Sm₈Cr₂Si₆N₂O₂₄ oxynitride has an apatite-like structure. The parameters of the hexagonal unit cell are a = 9,469 (5) and c = 6,890 (4) Å ; the space group is P6₃. The structure affinement has been carried to a R factor = 0,036 for 717 independent non-zero reflexions recorded with an automated diffractometer. The two Cr (III) atoms and two samarium atoms are distributed together among two 2 b crystallographic sites instead of occupying them in an ordered way., L'oxynitrure Sm₈Cr₂Si₆N₂O₂₄ possède une structure de type apatite. Les paramètres de la maille hexagonale sont a = 9,469 (5) et c = 6,890 (4) Å ; le groupe spatial est P6₃. L'affinement de la structure a été mené jusqu'à un facteur R = 0,036 pour 717 réflexions indépendantes non nulles mesurées grâce à un difïractomètre automatique. Les deux atomes de Cr (III) et deux atomes de samarium se répartissent sur deux sites cristallographiques 2 b au lieu de les occuper de façon ordonnée., Maunaye Marcel, Hamon Christian, L'Haridon Paul, Laurent Yves. Composés à structure apatite. IV. Étude structurale de l'oxynitrure Sm8Cr2Si6N2O24. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 99, 4, 1976. pp. 203-205.

Ca₂PI and Ca₃PI₃ have been selected for the structural study of M₂YI compounds and M₃₊ₓY₁₊ₓI₃₋ₓ (M = Ca, Sr, Ba — Y = P, As, Sb). Ca₂PI cristallises in the trigonal system (space group R[-3] m) and Ca₃PI₃ in the cubic system (space group I4₁32). We have described their structure in regard with the normal and defect NaCl superstructures. Ca₂PI is the first example with and anti α NaFeO₂ structure. The atomic order in Ca₃PI₃ leads to a new NaCl type superstructure., Ca₂PI et Ca₃PI₃ ont été choisis pour l'étude structurale des composés M₂YI et des phases M₃₊ₓY₁₊ₓI₃₋ₓ (M = Ca, Sr, Ba — Y = P, As, Sb). Ca₂PI cristallise dans le système rhomboédrique (groupe spatial R[-3]m) et Ca₃PI₃ dans le système cubique (groupe spatial I4₁32). On a décrit leur structure en la plaçant dans une systématique générale des surstructures normales et déficitaires dérivées de NaCl. Ca₂PI est le premier exemple de structure anti α NaFeO₂. L'ordre des différents atomes dans Ca₃PI₃ en fait un nouveau type de surstructure NaCl., Hamon Christian, Marchand Roger, Laurent Yves, Lang Jean. Étude d'halogénopnictures. III. Structure de Ca2PI et Ca3PI3. Surstructures de type NaCl. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 97, 1, 1974. pp. 6-12.

New possibilities for synthesis result from the introduction of nitrogen in the anionic sublattice of the apatites. They have been investigated from the structure of Sm₁₀Si₆N₂O₂₄. Because the nitrogen atoms are placed in the tetrahedral environment of the silicon atoms, their number may have a higher value. New compounds can thus be obtained where lanthanides and transition elements in a high oxydation state are simultaneously present. A lot of possibilities have been studied by considering the different crystallographic sites and their environment rather than the substitution mechanisms based on chemical analogies., L'introduction d'azote dans le réseau anionique des apatites ouvre de nouvelles perspectives de synthèse. Elles ont été envisagées à partir de la structure de Sm₁₀Si₆N₂O₂₄. La participation des atomes d'azote à l'environnement du silicium permet de prévoir une augmentation importante de leur nombre. Il est alors possible de préparer des composés dans lesquels interviennent simultanément des lanthanides et des éléments de transition dans un état d'oxydation élevé. On a étudié un ensemble de possibilités en considérant les divers sites cristallographiques et leur environnement plutôt qu'uniquement des mécanismes de substitutions fondés sur des analogies chimiques., Lang Jean, Marchand Roger, Hamon Christian, L'Haridon Paul, Guyader Jean. Composés à structure apatite. II. — Cristallochimie des silico-apatites azotées. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 98, 5, 1975. pp. 284-288.