Automated Identification and Classification of Stereochemistry: Chirality and Double Bond Stereoisomerism

Stereoisomers have the same molecular formula and the same atom connectivity and their existence can be related to the presence of different three-dimensional arrangements. Stereoisomerism is of great importance in many different fields since the molecular properties and biological effects of the stereoisomers are often significantly different. Most drugs for example, are often composed of a single stereoisomer of a compound, and while one of them may have therapeutic effects on the body, another may be toxic. A challenging task is the automatic detection of stereoisomers using line input specifications such as SMILES or InChI since it requires information about group theory (to distinguish stereoisomers using mathematical information about its symmetry), topology and geometry of the molecule. There are several software packages that include modules to handle stereochemistry, especially the ones to name a chemical structure and/or view, edit and generate chemical structure diagrams. However, there is a lack of software capable of automatically analyzing a molecule represented as a graph and generate a classification of the type of isomerism present in a given atom or bond. Considering the importance of stereoisomerism when comparing chemical structures, this report describes a computer program for analyzing and processing steric information contained in a chemical structure represented as a molecular graph and providing as output a binary classification of the isomer type based on the recommended conventions. Due to the complexity of the underlying issue, specification of stereochemical information is currently limited to explicit stereochemistry and to the two most common types of stereochemistry caused by asymmetry around carbon atoms: chiral atom and double bond. A Webtool to automatically identify and classify stereochemistry is available at http://nams.lasige.di.fc.ul.pt/tools.ph

Integrated Safety and Security Risk Assessment Methods: A Survey of Key Characteristics and Applications

Over the last years, we have seen several security incidents that compromised system safety, of which some caused physical harm to people. Meanwhile, various risk assessment methods have been developed that integrate safety and security, and these could help to address the corresponding threats by implementing suitable risk treatment plans. However, an overarching overview of these methods, systematizing the characteristics of such methods, is missing. In this paper, we conduct a systematic literature review, and identify 7 integrated safety and security risk assessment methods. We analyze these methods based on 5 different criteria, and identify key characteristics and applications. A key outcome is the distinction between sequential and non-sequential integration of safety and security, related to the order in which safety and security risks are assessed. This study provides a basis for developing more effective integrated safety and security risk assessment methods in the future

Uma inscrição votiva em língua lusitana

Dá-se notícia de um importante achado epigráfico relativo a uma inscrição votiva em língua lusitana onde estão contidas referências a divindades inéditas. Elabora-se uma tentativa de definição dessas divindades

DEIXAR-SE COMO HERANÇA PARA A HUMANIDADE, ISMAEL NERY E A FASE SURREALISTA

First, we introduce the painter Ismael Nery, the phases of his pictorial work,ideas and philosophical conceptions. Soon after, we delve deeper into a poem in prose anda surrealist drawing (Ismael Nery’s Testament). We focus on the various connectionsbetween the two works, highlighting the corresponding perfect unity between both. In thisdialogue between poetry and painting, passages extracted from literary and art critiques bythe poet Murilo Mendes and extracts from an interview given by Murilo Mendes to Vejamagazine in the seventies emphasize the meaning we want to convey. Finally, the use ofthe surrealist visual language by Nery to deal with his spiritual and apostolic concernsenhances this bridge between painting and literature.Inicialmente, apresenta-se o pintor Ismael Nery, as fases de sua obra pictórica esuas idéias e concepções filosóficas. No segundo momento, trata-se, mais especificamente, deum poema em prosa (“Última página” ou “Testamento Espiritual de Ismael Nery”) e umdesenho da fase surrealista (Testamento de Ismael Nery). Serão apontadas as várias ligações entreas duas obras, no sentido de observar a perfeita unidade existente entre elas. Nesse diálogoentre poesia e pintura, serão empregadas também algumas passagens de textos das críticas dearte e literária do poeta Murilo Mendes e ainda trechos de uma entrevista concedida por ele àrevista Veja nos anos 70. Ao final do trabalho, será destacado o uso do visual surrealista, porparte de Ismael, em benefício de seus interesses espirituais e apostólicos