Carbohydrate-derived iminium salt organocatalysts for the asymmetric epoxidation of alkenes

A new family of carbohydrate-based dihydroisoquinolinium salts has been prepared and tested for potential as asymmetric catalysts for the epoxidation of unfunctionalized alkene substrates, providing up to 57% ee in the product epoxides

Model theory of finite and pseudofinite groups

This is a survey, intended both for group theorists and model theorists, concerning the structure of pseudofinite groups, that is, infinite models of the first-order theory of finite groups. The focus is on concepts from stability theory and generalisations in the context of pseudofinite groups, and on the information this might provide for finite group theory

New biphenyl iminium salt catalysts for highly enantioselective asymmetric epoxidation: role of additional substitution and dihedral angle

New biaryl iminium salt catalysts for enantioselective alkene epoxidation containing additional substitution in the heterocyclic ring are reported. The effects upon conformation and enantioselectivity of this additional substitution, and the influence of dihedral angle in these systems, has been investigated using a synthetic approach supported by density functional theory. Enantioselectivities of up to 97% ee were observed

O caso da destruição das pinturas murais da sede da Fazenda Rialto, Bananal

This article is about the eighteenth century mural paintings at the headquarters of Fazenda Rialto, in Bananal, which were destroyed in 1996. These constituted one of the most important sets of ambient paintings with secular themes produced in the state of São Paulo during the period corresponding to the first cycle of coffee production. Orally attributed to the painter José Maria Villaronga y Panella, all that remains of these paintings are some photographs and dozens of fragments, impossible to reassemble. Studying the fragments of the paintings of Rialto as primary material documents, the main objective of this article is to identify the artistic, technical, and executive characteristics of three sets of murals attributed to a single painter. A methodology which combines laboratory tests and historical research on artistic techniques was adopted for objectively recognizing the artistic and artisan characteristics of the period and discussing the attribution of exclusive authorship to the work. The analytical systems adopted for this purpose were: examination with ultraviolet and infra-red radiation, optical microscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDS) to analyze its chemical elements. Issues related to the limitations on official Brazilian preservation activities for this category of artistic work were also discussed, reflecting on the development and changes in notions of historicity related to the preservation of works from the past and their methodological implications for conservation and restoration.Este artigo trata dos murais artísticos oitocentistas da sede da Fazenda Rialto, em Bananal, destruídos em 1996, que constituíam um dos mais importantes conjuntos de pinturas ambientais de temática profana produzidos no Estado de São Paulo no período correspondente ao primeiro ciclo da cultura do café. Atribuídas oralmente ao pintor José Maria Villaronga y Panella, dessas pinturas restaram apenas algumas fotografias e centenas de fragmentos, de impossível reassemblagem. Estudando-se os fragmentos de pintura da Rialto como documento material primário, o trabalho apresentado tem como principal objetivo a identificação das características artísticas e tecnoexecutivas de três conjuntos de murais tributados a um mesmo pintor. Para reconhecimento objetivo dos fazeres artístico-artesanais do período e discussão da atribuição de autoria exclusiva, adotou-se uma metodologia que combina exames laboratoriais e pesquisa histórica das técnicas artísticas. Os sistemas analíticos adotados para esse fim foram: exame com radiação ultravioleta e infravermelha, microscopia óptica, microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva (EDS) para análise química elementar. Discutem-se também questões relativas aos limites da ação preservacionista oficial brasileira sobre essa categoria de obra artística, refletindo sobre o desenvolvimento e as mudanças das noções de historicidade relativas à preservação dos bens do passado e suas implicações metodológicas nos conceitos de conservação e restauro

O território paulista na iconografia oitocentista: mapas, desenhos e fotografias. análise de uma herança cotidiana

This paper presents a study about the cartography elaborated to represent São Paulos territory during the 19th century. The author seeks to show the permanence of cultural values related to the colonial period by analyzing some cartographical models, which are not necessarily linked to a cartographic school. In this context, the author seeks to identify the formative values of the regional territorial space, the cultural identity of the common Man and the specific needs of his or her daily life

Educomunicação e suas áreas de intervenção: Novos paradigmas para o diálogo intercultural

oai:omp.abpeducom.org.br:publicationFormat/1O material aqui divulgado representa, em essência, a contribuição do VII Encontro Brasileiro de Educomunicação ao V Global MIL Week, da UNESCO, ocorrido na ECA/USP, entre 3 e 5 de novembro de 2016. Estamos diante de um conjunto de 104 papers executivos, com uma média de entre 7 e 10 páginas, cada um. Com este rico e abundante material, chegamos ao sétimo e-book publicado pela ABPEducom, em seus seis primeiros anos de existência. A especificidade desta obra é a de trazer as “Áreas de Intervenção” do campo da Educomunicação, colocando-as a serviço de uma meta essencial ao agir educomunicativo: o diálogo intercultural, trabalhado na linha do tema geral do evento internacional: Media and Information Literacy: New Paradigms for Intercultural Dialogue

Reconstruire

Situer des évènements dans le temps est une question essentielle en science forensique, de même que le transfert et l'identification. En effet, si une personne déclare avoir été sur les lieux d'un crime à un autre moment que l'évènement en question, la trace laissée (transfert) sur les lieux par cette personne (identification) perd toute signification. La pertinence de la trace est donc étroitement liée à la notion de temps. Les difficultés rencontrés lors de l'étude de la datation de différents type de traces ont crées une controverse mondiale sur la validité des méthodes proposées jusqu'ici, particulièrement en regard de la responsabilité de l'expert scientifique face à la justice. Si l'on considère la récurrence de cette problématique en sciences forensiques, une approche systématique ainsi qu'une meilleure compréhension fondamentale de la détermination de l'âge d'une trace est définitivement nécessaire. Cela représente un grand défi, puisque les processus de vieillissement sont influencés par plusieurs facteurs qui peuvent considérablement accélérer ou ralentir le vieillissement. Ceux-ci devront être étudiés de manière approfondie et peuvent être classés en trois groupes principaux : (i) la composition initiale de la trace, (ii) le type de substrat sur lequel se trouvent les traces, et (iii) les conditions de stockage. Pour ces raisons, l'objectif est donc plus de déterminer un intervalle de temps durant lequel la trace a été déposée, plutôt qu'une date précise. Finalement, une interprétation des résultats selon une approche probabiliste (par ex. basée sur une inférence de type Bayesienne sous deux hypothèses alternatives) semble la plus appropriée. Le développement de cette approche globale fait l'objet d'un ambitieux programme de recherche soutenu par le Fonds National Suisse de la Recherche Scientifique