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The reaction of CO2 and epoxides to form organic carbonates requires Lewis base catalysts, such as tetrabutylammonium halides (TBAX). Their activity and selectivity towards cyclic carbonates can be strongly reinforced with Lewis acids, as for example, Salen or porphyrin metallic complexes. We developed a series of nitrogen Schiff base (N-SB) compounds1 that forms a family of ligands that combines properties of both, Salen flexibility and porphyrins nitrogen coordination sphere. Herein, we present the synthesis and characterization of pyrrole containing Nitrogen-Schiff Base (N-SB) ligands. XRay analysis showed monomeric or dimeric helical structures, according with the coordination mode of the zinc centre that can be tetra or pentacoordinated. Combined to TBAX, the zinc N-SB complexes proved to be efficient and selective co-catalysts for the valorisation of CO2 into cyclic carbonates. The optimization of the reaction parameters was carried out with styrene oxide, and solvent free reactions allowed very high yields (up to 97%) using very small catalyst/co-catalyt amounts (less than 0.2mol%)2. Moreover, the robustness of these zinc complexes allowed various catalytic runs four days long, without any purification, just adding new loadings of styrene oxide. The reaction scope was also enlarged to other epoxides.

SSCI-VIDE+CDURABLE:ING+LCH:ATU:MAP; International audience; The reaction of CO2 and epoxides to form organic carbonates requires Lewis base catalysts, such as tetrabutylammonium halides (TBAX). Their activity and selectivity towards cyclic carbonates can be strongly reinforced with Lewis acids, as for example, Salen or porphyrin metallic complexes. We developed a series of nitrogen Schiff base (N-SB) compounds1 that forms a family of ligands that combines properties of both, Salen flexibility and porphyrins nitrogen coordination sphere. Herein, we present the synthesis and characterization of pyrrole containing Nitrogen-Schiff Base (N-SB) ligands. XRay analysis showed monomeric or dimeric helical structures, according with the coordination mode of the zinc centre that can be tetra or pentacoordinated. Combined to TBAX, the zinc N-SB complexes proved to be efficient and selective co-catalysts for the valorisation of CO2 into cyclic carbonates. The optimization of the reaction parameters was carried out with styrene oxide, and solvent free reactions allowed very high yields (up to 97%) using very small catalyst/co-catalyt amounts (less than 0.2mol%)2. Moreover, the robustness of these zinc complexes allowed various catalytic runs four days long, without any purification, just adding new loadings of styrene oxide. The reaction scope was also enlarged to other epoxides.

Multimodal Sentiment Analysis (MuSe) 2021 is a challenge focusing on the tasks of sentiment and emotion, as well as physiological-emotion and emotion-based stress recognition through more comprehensively integrating the audio-visual, language, and biological signal modalities. The purpose of MuSe 2021 is to bring together communities from different disciplines; mainly, the audio-visual emotion recognition community (signal-based), the sentiment analysis community (symbol-based), and the health informatics community. We present four distinct sub-challenges: MuSe-Wilder and MuSe-Stress which focus on continuous emotion (valence and arousal) prediction; MuSe-Sent, in which participants recognise five classes each for valence and arousal; and MuSe-Physio, in which the novel aspect of ‘physiological-emotion’ is to be predicted. For this year’s challenge, we utilise the MuSe-CaR dataset focusing on user-generated reviews and introduce the Ulm-TSST dataset, which displays people in stressful depositions. This paper also provides detail on the state-of-the-art feature sets extracted from these datasets for utilisation by our baseline model, a Long Short-Term Memory-Recurrent Neural Network. For each sub-challenge, a competitive baseline for participants is set; namely, on test, we report a Concordance Correlation Coefficient (CCC) of .4616 CCC for MuSe-Wilder; .5088 CCC for MuSe-Stress, and .4908 CCC for MuSe-Physio. For MuSe-Sent an F1 score of 32.82% is obtained.

A cultura da soja representa grande parcela econômica na produção agrícola Brasileira. No Rio Grande do Sul (RS) a cada safra verifica-se um aumento da área ocupada com o cultivo. No ambiente de terras baixas a cultura abrange 5,4 milhões hectares correspondendo a cerca de 20% da área total do Estado. O uso de cultivares transgênicas que tem como principal vantagem o controle de insetos alvo, além da redução do número de aplicações de inseticidas ao longo do cultivo. Porém, o alto custo do valor da semente transgênica é considerado a principal desvantagem na adoção dessa tecnologia. O objetivo deste trabalho foi avaliar o desempenho de cultivares RR1 e RR2 em relação à ocorrência de lagartas e percevejos, bem como avaliar o custo de produção. O experimento foi instalado na Embrapa Clima Temperado nas safras 2014/2015 e 2015/2016 com as cultivares convencional (BMX Potência (RR1 6.7)) e as isolinhas Bt (BMX Ponta (IPRO 6.6) e BMX Vanguarda (IPRO 6.0)). A cultivar BMX Potência apresentou maior incidência de lagartas desfolhadoras e o do percevejo Nezara viridula, sendo a cultivar mais indicada, entre as avaliadas, para o ambiente de terras baixas do Sul do RS, devido à produtividade e lucratividade. Made available in DSpace on 2020-03-13T15:59:54Z (GMT). No. of bitstreams: 1 Soybean-cv-in-IPM-in-TB-agroecossistem.pdf: 860943 bytes, checksum: 58e21305c57c487b786ce295706f1fb0 (MD5) Previous issue date: 2020 Desempenho de cultivares de soja no manejo integrado de pragas no agroecossistema de terras baixas.

SSCI-VIDE+CDFA+ADN:LCH:NES; National audience; None

SSCI-VIDE+CDFA:ING+MAP:ATU:LCH; National audience; The insertion of CO2 into epoxides requires the cooperation between a Lewis acid catalyst and a Lewis base catalyst1, usually a quaternary ammonium halide. The study of this reaction has focused on the development of new Lewis acid catalysts, among which salen complexes2 and metalloporphyrins3 are the most representative. Nitrogen Schiff base complexes (N-SB)4,5,6, that combines the properties of salens (flexibility) and porphyrins (full-nitrogen coordinating sphere), feature a new class of complexes with promising perspectives in the cycloaddition of CO2 over epoxides. Pyrrole-based Schiff Base zinc complexes (Zn-N-SB) have been synthesized using pentadentate and tetradentate ligands and fully characterized using conventional techniques (NMR, IR, XRD). Depending on the nature of the ligand, monomeric or dimeric species are obtained, showing unexpected geometries. In addition to their synthesis and characterization, the present communications will report their use as Lewis acids, along with tetrabutylammonium halides as Lewis bases, in the synthesis of styrene cyclic carbonate from CO2, affording yields up to 90%.

SSCI-VIDE+CDFA+LCH:SZA; International audience; Carbon dioxide can be used as a renewable carbon source to prepare many organic compounds. Among them, useful cyclic carbonates can be obtained by the catalytic CO2 addition to epoxides. Various homogeneous catalysis can be used, including salen derivatives combined to ammonium halides. We developed a salen nitrogen analog and prepared its chromium complexes [1] that catalyzed the CO2 insertion to epoxides, leading to cyclic carbonates or polycarbonates. In order to get selective catalyst to cyclic carbonates, we focused on nitrogen Schiff base complexes of zinc.

SSCI-VIDE+CDFA+SZA:LCH:IKA; International audience; A new and mild method of glycerol acetalization reaction with various carbonyl compounds catalyzed by the cheap and simple iron catalyst FeCl3 center dot 6H(2)O has been developed. This method which consists in the transformation of glycerol to cyclic acetals under mild conditions, with or without solvent, allowed interesting results: glycerol acetalization using ketones leads to the corresponding 1,3-dioxolanes with a very good selectivity (97-100%), whereas mixture of 1,3-dioxolanes and 1,3-dioxanes was formed when using aldehydes, with a good selectivity toward 1,3-dioxanes up to 76%. (C) 2017 Elsevier B.V. All rights reserved.

SSCI-VIDE+CDFA+LCH; International audience; Our studies focus on nitrogen Schiff bases since these N4 ligands are similar to porphyrins (N4 ligands) and Salen compounds (N2O2 ligands). Nitrogen Schiff bases (BS-4N), present an open structure that can be flexible and chiral, when prepared from the corresponding chiral diamine by a Schiff condensation with an aldehyde. Thus, we developed a series of nitrogen Schiff bases (BS-4N) complexes using various metals (Ni, Co, Cu, Zn, Mn, Fe) and characterized them by spectroscopic methods (NMR, IR, Raman, Mössbauer) and XRay when suitable crystals were obtained [1].As many catalysts are described with porphyrins and salen ligands, the prepared BS-4N complexes may have interesting catalytic properties. The presentation will focus on the use of Nitrogen Schiff Base complexes as catalysts for the carbon dioxide addition to epoxides and the optimization of experimental conditions to form selectively cyclic carbonates. The reactions were carried in liquid phase and supercritical conditions, thus having CO2 as solvent and substrate [2-3]. A theoretical approach on the reaction mechanism will aslo be discussed [4].

SSCI-VIDE+CDFA+LCH; National audience; None

Vorgeschichte: Bei einer zuvor gesunden 58-jährigen Patientin waren vor zwei Monaten palmar betonte Hyperkeratosen, Rhagaden und erythrosquamöse Hautveränderungen aufgetreten, die auf eine bei auswärtiger Verdachtsdiagnose einer systemischen Sklerose eingeleitete Therapie mit Amlodipin,[zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh); 30. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh); 26. Jahrestagung der Gesellschaft für Kinder- und Jugendrheumatologie (GKJR)