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The challenge for decreasing the emissions of compression ignition engines now remains mainly on NOx control. If the Lean NOx Trap (LNT) and Selective Catalytic Reduction by Urea (Urea-SCR) are very efficient, their extra-cost and management are a major issue for the OEMs. In that context, the selective catalytic reduction by hydrocarbons (HC-SCR) appears to be an interesting alternative solution, with a more limited NOx conversion efficiency but an easier packaging (diesel fuel as a reductant) and a limited price (reasonable coating cost / no PGM). In the framework of the RedNOx project, a prototype catalyst made of 2% silver on Alumina coated on cordierite was manufactured and tested on a synthetic gas bench. In parallel, an exhaust implementation study has been led to ensure the most suited conditions for injection. Thanks to SGB and simulation results, adapted engine tests have been designed and performed. If the results on SGB are consistent with the literature with a maximum NOx conversion reaching about 70% and an operating range between 300 and 500°C, first engine results were very disappointing showing efficiencies lower than 15% for all the operating points. Three guidelines for improving these results were identified and studied: • The way the reductant is introduced in the exhaust, especially the discontinued HC delivery due to the injection pattern • The gas velocity: unusual small GHSV values for automotive applications are needed to ensure a good NOx conversion rate. • The nature of the used reductant. Diesel fuel (ULSD) compared with decane lowers the efficiency, but synthetic Diesel fuel (SD) and, moreover, ethanol, largely improve it, especially for high GHSV.

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.

The progression of stem cells to proliferating progenitor cells and finally to a quiescent differentiated state is a hallmark of organ development. This process proceeds through distinct steps and is regulated through cell-cell interactions and by systemically and locally acting factors. We have established a cell culture system which recapitulates features of mammary gland development in vitro and allows the comparison of three characteristic differentiation stages. Cell fate decisions relating to proliferation and differentiation are dependent on the function of proteins in the nucleus. Therefore, we have applied proteomic approaches, including 1- and 2-DE coupled with MS and a gel-free system, called protein sequence tag technology (PST), to assess the changes in the nuclear protein composition during differentiation of mammary epithelial cells. We identified about 250 individual proteins which are present in the nucleus of proliferating and functionally differentiated mammary epithelial cells. We functionally categorised the differentially expressed proteins and identified a multitude of proteins that regulate gene expression at the transcriptional or post-transcriptional level. This analysis greatly enriches our global view of the dynamic changes of nuclear proteins during the development of mammary epithelial cells and suggests models for the control of differentiation-specific protein expression.

International audience; Le renouvellement de la technologie dans les enseignements est perceptible dans l'étiquetage diversifié de l'offre de cours (« technologie », « technologies », « technosciences », « sciences de l'ingénieur », « sciences industrielles de l’ingénieur », « sciences et technologies de l’ingénieur », etc.). Il s’accompagne de la révision des contenus qui tient compte des mutations des pratiques sociotechniques contemporaines, de la volonté de faire de l’éducation technologique une composante de la formation générale, mais aussi des rapports avec les enseignements scientifiques (intégration des sciences et de la technologie, référence aux technosciences). Les contenus sont également renouvelés par la prise en considération des nouveaux enjeux associés aux problématiques sociétales telles que le développement durable. Tout en faisant le point sur les problématiques didactiques associées à ces changements et en contribuant au renouvellement des réflexions sur l’enseignement et l’apprentissage de la technologie, cette approche franco-québécoise vise à proposer des perspectives de recherche et d’expertise didactiques futures.

About 25% of open reading frames in fully sequenced genomes are estimated to encode transmembrane proteins that represent valuable targets for drugs. However, the global analysis of membrane proteins has been proven to be problematic, e.g., because of their very amphiphilic nature. In this paper, we show that the recently published Protein Sequence Tag (PST) technology combined with an efficient sample preparation is a powerful method to perform protein analysis of highly enriched membrane fractions. The PST approach is a gel-free proteomics tool for the analysis of proteins, which relies on a "sampling" strategy by isolating N-terminal protein sequence tags from cyanogen bromide cleaved proteins. The identification of these N-terminal PST peptides is based on LC-MS/MS. The effectiveness of the technology is demonstrated for a membrane fraction, which was isolated from crude mitochondria of yeast after alkaline sodium carbonate treatment. The PST approach performed on this fraction analyzed 148 proteins, whereas 84% are identified as membrane proteins. More interestingly, among these membrane proteins 56% are predicted to be of low abundance. These encouraging results are an important step toward the development of a quantitative PST approach (qPST) for the differential display of membrane protein analysis.

A novel method for the isolation of protein sequence tags to identify proteins in a complex mixture of hydrophobic proteins is described. The PST (Protein Sequence Tag) technology deals with the isolation and MS/MS based identification of one N-terminal peptide from each polypeptide fragment generated by cyanogen bromide cleavage of a mixture of proteins. PST sampling takes place after sub-cellular fractionation of a complex protein mixture to give enrichment of mitochondrial proteins. The method presented here combines effective sample preparation with a novel peptide isolation protocol involving chemical and enzymatic cleavage of proteins coupled to chemical labeling and selective capture procedures. The overall process has been very successful for the analysis of complex mixtures of hydrophobic proteins, particularly membrane proteins. This method substantially reduces the complexity of a protein digest by "sampling" the peptides present in the digest. The sampled digest is amenable to analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS). Methods of "sampling" protein digests have great value' if they can provide sufficient information to identify substantially all of the proteins in the sample while reducing the complexity of the sample to maximize the efficient usage of LC-MS/MS capacity. The validity of the process is demonstrated for mitochondrial samples from S. cerevisiae. The proteins identified by the PST technology are compared to the proteins identified by the conventional technology 2-D gel electrophoresis as a control.

A convenient, low cost, large scale synthesis of (L)-β-cyclopropylalanine is reported.

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

International audience; FTIR spectroscopy was applied to the investigation of the nitrosyl complexes formed with the extra-framework iron species in Fe-ferrierite (Fe-FER). To clarify the loading effect oil the nature Of file species formed. six ferrierites with Fe loadings varying between 0 and 3.7 wt % were prepared via ionic exchange and investigated. A Fe/SiO(2) and a Fe-FER sample containing iron oxide were also Studied for comparison purposes. Adsorption of NO on Fe-FER (containing no iron oxide species) gives different nitrosyl species. and different iron sites call be evidenced depending on the iron concentration. The bands are assigned to mononitrosyl oil iron whose oxidation state is determined to be +2 thanks to Mossbauer spectroscopy. In particular, one specific Fe(2+)-cation (typical of a highly loaded sample) appears to be easily converted to Fe(3+) upon oxygen treatment, which makes these sites excellent candidates for catalytically active redox sites.

Comparative proteome profiling using stable isotope peptide labelling and mass spectrometry has emerged as a promising strategy. Here, we show the broad potential of our proprietary protein sequence tag (PST) technology.* A special feature of PST is its ability to detect a wide variety of proteins including the pharmaceutically relevant membrane and nuclear proteins. This procedure addresses a similar number of proteins, compared to the multidimensional protein identification technology approach, but offers additionally a quantitative analysis with its recently developed quantitative PST version.

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.

International audience