94 research outputs found
La bande dessinée en Inde : enjeux et stratégies en classe de français à travers deux études de cas
Get PDFCet article étudie les apports de la bande dessinée dans deux établissements et deux filières d’études différentes à Mumbai. La première est une filière de licence, avec le français comme langue facultative (niveau A2) et la deuxième, un cours de français langue étrangère, niveau A2+, dispensé à l’université. En raison de la nouveauté du genre dans le cursus universitaire, la chercheure s’intéresse à analyser et évaluer la réception et le rôle de la bande dessinée au sein de ces programmes. Dans le premier cas, la bande dessinée retenue au programme est Tintin et Les Cigares du Pharaon et dans le deuxième, il s’agit des extraits de Persepolis de Marjane Satrapi. Le corpus est composé de questionnaires et d’entretiens avec les deux enseignants concernés. Les résultats s’avèrent très intéressants et prometteurs. Non seulement, la bande dessinée s’écarte des manuels normalement prescrits et par là apporte une nouveauté, mais par sa richesse iconographique et ses qualités transversales, trouve une place favorable auprès de l’apprenant du FLE. L’influence de la bande dessinée sur les pratiques pédagogiques des enseignants est également étudiée. Les deux enseignants en question s’emparent de cette ressource de façons très différentes, pour travailler des compétences variées, tant sur le plan linguistique que culturel et interculturel, en lien avec les objectifs d’apprentissage et les besoins de leur public. Dans les deux cas, la bande dessinée ouvre la voie pour une vraie aventure pédagogique et justifie bien sa place dans les programmes étudiés.Synergies Espagne n° 14 - 2021 p. 249-265 - GERFLINT -
URL: https://gerflint.fr/Base/Espagne14/badrinathan.pd
Photochemistry of dibenzothiophene-based sulfilimines
Get PDFAzides have been the most extensively investigated precursors for the photochemical generation of nitrenes. Direct spectroscopic studies as well as indirect product studies have provided adequate evidence for the intermediacy of nitrenes, in at least some azides. On the other hand, less is known on the photochemical decomposition of sulfilimines. A systematic study of the potential of sulfilimines as nitrene precursors is undertaken in the current work. N-Benzoyl, N-acetyl, N-trifluoroacetyl, N-tosyl and N-mesyl derivatives of dibenzothiophene sulfilimine have been synthesized and analyzed for their photochemical reactivities. The extended UV-Vis absorption of the dibenzothiophene moiety allows for long wavelength photolysis and consequently provides access to a wide variety of nitrenes including the parent N-H version. The syntheses of N-H and the N-formyl derivatives of dibenzothiophene sulfilimine have also been achieved.;It has been previously established that benzoyl and acetylnitrenes have singlet ground states while tosylnitrene has a triplet ground state. Our studies using time-resolved IR spectroscopy provides direct evidence for singlet and triplet nitrenes from N-benzoyl and N-acetyl sulfilimine derivatives. Product studies indicate that decay via the singlet nitrene channel is the major process. N-tosyl and N-mesyl sulfilimine derivatives differ from the above two, in that, the primary decay channel is triplet nitrene capture. In the case of N-trifluoroacetyl analogue, we observed products due to both singlet and triplet nitrene intermediacy. The products observed depend on the ground state multiplicities of the corresponding nitrenes generated. Theoretical calculations were performed to estimate the singlet-triplet energy splittings for mesyl and trifluoroacetylnitrene. Coupled-cluster calculations predict a triplet ground state for mesylnitrene and a closely spaced singlet and triplet energies for trifluoroacetylnitrene. Hence, we observe products from both spin states in the case of trifluoroacetylnitrene while predominantly from the triplet in the case of mesylnitrene. The calculations support our inference from product studies.;All the sulfilimines analyzed indicate a potential for S-N bond cleavage from the excited triplet state of the sulfilimine. This is in line with our proposed mechanism for the photochemical unimolecular S-O bond cleavage of dibenzothiophene-S-oxide leading to O( 3P).</p
A novel approach to identify the performance & security in various routing protocols
No full textPhotochemistry of N-Acetyl-, N-Trifluoroacetyl-, N- Mesyl-, and N-Tosyldibenzothiophene Sulfilimines
Get PDFTime-resolved infrared (TRIR) spectroscopy, product studies, and computational methods were applied to the photolysis of sulfilimines derived from dibenzothiophene that were expected to release acetylnitrene, trifluoroacetylnitrene, mesylnitrene, and tosylnitrene. All three methods provided results for acetylnitrene consistent with literature precedent and analogous experiments with the benzoylnitrene precursor, i.e., that the ground-state multiplicity is singlet. In contrast, product studies clearly indicate triplet reactivity for trifluoroacetylnitrene, though TRIR experiments were more ambiguous. Product studies suggest that these sulfilimines are superior sources for sulfonylnitrenes, which have triplet grounds states, to the corresponding azides, and computational studies shed light on the electronic structure of the nitrenes.Reprinted (adapted) with permission from The Journal of Organic Chemistry, 73(12); 4398-4414. Doi: 10.1021/jo702654q. Copyright 2008 American Chemical Society.</p
Optimized Ensemble Approach for Multi-model Event Detection in Big data
Get PDFEvent detection acts an important role among modern society and it is a popular computer process that permits to detect the events automatically. Big data is more useful for the event detection due to large size of data. Multimodal event detection is utilized for the detection of events using heterogeneous types of data. This work aims to perform for classification of diverse events using Optimized Ensemble learning approach. The Multi-modal event data including text, image and audio are sent to the user devices from cloud or server where three models are generated for processing audio, text and image. At first, the text, image and audio data is processed separately. The process of creating a text model includes pre-processing using Imputation of missing values and data normalization. Then the textual feature extraction using integrated N-gram approach. The Generation of text model using Convolutional two directional LSTM (2DCon_LSTM). The steps involved in image model generation are pre-processing using Min-Max Gaussian filtering (MMGF). Image feature extraction using VGG-16 network model and generation of image model using Tweaked auto encoder (TAE) model. The steps involved in audio model generation are pre-processing using Discrete wavelet transform (DWT). Then the audio feature extraction using Hilbert Huang transform (HHT) and Generation of audio model using Attention based convolutional capsule network (Attn_CCNet). The features obtained by the generated models of text, image and audio are fused together by feature ensemble approach. From the fused feature vector, the optimal features are trained through improved battle royal optimization (IBRO) algorithm. A deep learning model called Convolutional duo Gated recurrent unit with auto encoder (C-Duo GRU_AE) is used as a classifier. Finally, different types of events are classified where the global model are then sent to the user devices with high security and offers better decision making process. The proposed methodology achieves better performances are Accuracy (99.93%), F1-score (99.91%), precision (99.93%), Recall (99.93%), processing time (17seconds) and training time (0.05seconds). Performance analysis exceeds several comparable methodologies in precision, recall, accuracy, F1 score, training time, and processing time. This designates that the proposed methodology achieves improved performance than the compared schemes. In addition, the proposed scheme detects the multi-modal events accurately
Lygodium flexuosum extract down regulates the expression of proinflammatory cytokines in CCl4–induced hepatotoxicity
No full textAbstractObjectiveTo examine the downregulation of proinflammatory cytokines in a time dependant manner on carbon tetrachloride induced toxicity in experimental animals.MethodsCCl4 (150 μL/100 g) was dissolved in corn oil (1:1 v/v %) and administered orally. Group I was treated as normal control and received corn oil on 8th day. Group II was toxic control and was given a single dose of CCl4 on 8th days. Group III was treated with Lygodium flexuosum (L. flexuosum) n-hexane extract (200 mg/kg) for 8 days and on 8th day a single dose of CCl4 was received. Group IV (negative control) received L. flexuosum n-hexane extract (200 mg/kg) alone for 8 days.ResultsTreatment with n-hexane extract prior to the administration of CCl4 significantly prevented an increase in serum AST, ALT, LDH activity and lipid peroxidation and prevented the depletion of glutathione (GSH). Rats treated with L. flexuosum had reduced mRNA levels of TGF-β1, TNF-α and IL-1β genes in liver of CCl4 intoxicated rats when compared to CCl4 control as evidenced by RT-PCR.ConclusionsThe data suggest that L. flexuosum, a widely available fern, significantly reduces CCl4 induced acute hepatotoxicity by down-regulating the expression of pro-inflammatory cytokines in rats
Flotation of coking coal fines for low ash metallurgical coke applications
No full textLow Ash Metallurgical Coke (LAM Coke) finds wide applications in iron and steel foundries, non-ferrous metal castings, lead and zinc smelters, secondary steel production, chemical and ferro-alloy plants and pig iron production. One of the major specifications of the LAM coke is that ash in it should be < 11.0%. An attempt was made to produce a concentrate of < 11.0% ash from the fines (< 0.5mm), a feed to conventional flotation circuit in an operating coking coal washery, by grinding and flotation. Process parameters such as mesh-of-grind, collector and frother dosages were optimized. Coking coal sample analyzing 24.90% ash was beneficiated by grinding it to 85% passing 100 µm followed by flotation. A concentrate of 10.33% ash with 56.54% yield could be obtained using diesel as collector at 0.605 kg/t and frother at 0.0867 kg/t in the flotation which involves three-stage cleaning of rougher concentrate in order to obtain the final concentrate of required ash content. The concentrate produced could be utilized for making LAM Coke
Flotation Kinetics of Sillimanite and Garnet
No full textSillimanite is being produced from the heavy mineral beach sands at Orissa Sands Complex, Orissa, India (M/s. Indian Rare Earths Limited) by flotation using oleic acid as collector. It was found that garnet inevitably contaminates sillimanite mineral concentrate. A study was made on the flotation kinetics of different natural grain sizes of sillimanite and garnet for better understanding and control of the flotation process to separate these two minerals more efficiently. Kinetic data on different grain sizes of sillimanite indicate that it follows the non-integral-order rate equation and the rate constant was 0.0704 min-1 and similar studies on garnet indicate that its flotation process can be assimilated in the first order rate equation and the corresponding rate constant was found to be 0.0347 min-1. The study shows that the rate constants for each of the sizes considered for both sillimanite and garnet were found to be different under the same experimental conditions and that sillimanite floats much faster at all the natural grain sizes, twice as fast as garnet
ChemInform Abstract: Organoboranes. Part 56. Systematic Study of the Reactions of 1- Alkenylboronic Esters with Representative Organolithium and Grignard Reagents to Provide an Efficient, Selective Synthesis of Organyl-1- alkenylborinic Esters.
No full textPhotochemistry of <i>N-</i>Acetyl-, <i>N-</i>Trifluoroacetyl-, <i>N-</i> Mesyl-, and <i>N-</i>Tosyldibenzothiophene Sulfilimines
No full textTime-resolved infrared (TRIR) spectroscopy, product studies, and computational methods were applied to the photolysis of sulfilimines derived from dibenzothiophene that were expected to release acetylnitrene, trifluoroacetylnitrene, mesylnitrene, and tosylnitrene. All three methods provided results for acetylnitrene consistent with literature precedent and analogous experiments with the benzoylnitrene precursor, i.e., that the ground-state multiplicity is singlet. In contrast, product studies clearly indicate triplet reactivity for trifluoroacetylnitrene, though TRIR experiments were more ambiguous. Product studies suggest that these sulfilimines are superior sources for sulfonylnitrenes, which have triplet grounds states, to the corresponding azides, and computational studies shed light on the electronic structure of the nitrenes
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