Mechanochemical interconversion between discrete complexes and coordination networks - formal hydration/dehydration by LAG

Using a small planetary ball mill, liquid-assisted grinding (LAG) of metal salts or oxides (ZnO, CdO, CdCO3, Cu(OAc)(2)center dot H2O, Co(OAc)(2)center dot 4H(2)O, Mn(OAc)(2)center dot 4H(2)O, Ni(OAc)(2)center dot 4H(2)O, FeSO4 center dot 7H(2)O) with two equivalents of isonicotinic acid (HINA) and small amounts of water ( up to 5.6 molar equivalents) gave discrete aquo complexes trans-[M(INA)(2)(OH2)(4)] (M = Zn, Cd, Cu, Fe, Co, Ni, Mn) efficiently within 30 min. For M = Zn, Cd and Cu these complexes readily undergo reversible formal dehydration to the extended network structures [M(INA)(2)] (M = Zn, Cu) or [Cd(INA)(2)(OH2)]center dot DMF by further LAG with non-aqueous liquids such as methanol or DMF. Overall, the mechanochemical dehydrations are more effective than heating or immersion in bulk solvents. The work demonstrates a two-step mechanochemical synthesis of coordination networks via discrete aquo complexes which may be preferable to single step reactions or grinding-annealing procedures in some cases. For example, the two step method was the only way to prepare [Cd(INA)(2)(OH2)]center dot DMF mechanochemically and the porous network Cu(INA)(2) could not be obtained from the aquo complex by heating.

Flawed Premises and Unexpected Consequences: Support of Regional Languages in Europe:Support of Regional Languages in Europe

This article discusses the relationship between three language communities in Europe with variant levels of official recognition, namely Kashub, Sorb, and Silesian, and the institutions of their host states as regards their respective use, promotion, and revital-ization. Most language communities across the world campaign for recognition within a geographic/political region, or on the basis of a historic/group identity to ensure their language's use and status. The examples discussed here illustrate that language recognition and policies resulting therefrom and promoting official monolin-gualism strengthen the symbolic status of the language but contribute little to the functionality of language communities outside the area. As this article illustrates, in increasingly multilingual societies, language policies cut off its speakers from the political, economic, and social opportunities accessible through the medium of languages that lack official recognition locally. © 2014 Taylor & Francis Group, LLC.

Aza-annulation of enaminones with crotonyl chloride - Formal reversal of regioselectivity.

The regiochemistry of aza-annulation of enaminones with alpha,beta-unsaturated acid chlorides bearing hydrogen atoms on the gamma-carbon is reversed when triethylamine is used as mediator. When the reaction was carried out at lower temperatures as 3-acyl beta,gamma-unsaturated compound could be isolated which cyclised to the desired product under thermal or basic conditions. The nature of this intermediate strongly suggests that a vinyl ketene is the active acylating agent. (C) 1997 Elsevier Science Ltd.

The Complexity of MAP Inference in Bayesian Networks Specified Through Logical Languages

We study the computational complexity of finding maximum a posteriori configurations in Bayesian networks whose probabilities are specified by logical formulas. This approach leads to a fine grained study in which local information such as context-sensitive independence and determinism can be considered. It also allows us to characterize more precisely the jump from tractability to NP-hardness and beyond, and to consider the complexity introduced by evidence alone.

Model-based systems engineering: a system for traffic & environment

The contemporary world is crowded of large, interdisciplinary, complex systems made of other systems, personnel, hardware, software, information, processes, and facilities. The Systems Engineering (SE) field proposes an integrated holistic approach to tackle these socio-technical systems that is crucial to take proper account of their multifaceted nature and numerous interrelationships, providing the means to enable their successful realization. Model-Based Systems Engineering (MBSE) is an emerging paradigm in the SE field and can be described as the formalized application of modelling principles, methods, languages, and tools to the entire lifecycle of those systems, enhancing communications and knowledge capture, shared understanding, improved design precision and integrity, better development traceability, and reduced development risks. This thesis is devoted to the application of the novel MBSE paradigm to the Urban Traffic & Environment domain. The proposed system, the GUILTE (Guiding Urban Intelligent Traffic & Environment), deals with a present-day real challenging problem “at the agenda” of world leaders, national governors, local authorities, research agencies, academia, and general public. The main purposes of the system are to provide an integrated development framework for the municipalities, and to support the (short-time and real-time) operations of the urban traffic through Intelligent Transportation Systems, highlighting two fundamental aspects: the evaluation of the related environmental impacts (in particular, the air pollution and the noise), and the dissemination of information to the citizens, endorsing their involvement and participation. These objectives are related with the high-level complex challenge of developing sustainable urban transportation networks. The development process of the GUILTE system is supported by a new methodology, the LITHE (Agile Systems Modelling Engineering), which aims to lightening the complexity and burdensome of the existing methodologies by emphasizing agile principles such as continuous communication, feedback, stakeholders involvement, short iterations and rapid response. These principles are accomplished through a universal and intuitive SE process, the SIMILAR process model (which was redefined at the light of the modern international standards), a lean MBSE method, and a coherent System Model developed through the benchmark graphical modeling languages SysML and OPDs/OPL. The main contributions of the work are, in their essence, models and can be settled as: a revised process model for the SE field, an agile methodology for MBSE development environments, a graphical tool to support the proposed methodology, and a System Model for the GUILTE system. The comprehensive literature reviews provided for the main scientific field of this research (SE/MBSE) and for the application domain (Traffic & Environment) can also be seen as a relevant contribution.

Apropriação do português por adultos eslavófonos: o tempo e o aspeto

As alterações no panorama social português que ocorreram no virar do milénio, marcadas pela chegada massiva de imigrantes provenientes de países que não tinham laços históricos e linguísticos com Portugal – com destaque para as comunidades do Leste europeu –, vieram colocar novos desafios à sociedade e à escola portuguesas. Com o propósito de caracterizar o perfil de apropriação da Língua Portuguesa (LP) de aprendentes adultos eslavófonos residentes em Portugal, foram recolhidos 87 questionários e testes linguísticos junto de adultos falantes de línguas eslavas que frequentavam cursos de LP em contexto formal/ não formal. Complementarmente, foram realizadas 17 entrevistas a aprendentes e professores. A análise de dados, de carácter quantitativo e qualitativo, centrou-se em três eixos fundamentais: a) o perfil de apropriação da LP; b) a gestão dos repertórios linguísticos; e c) as dificuldades manifestadas na apropriação, compreensão e uso do sistema temporal-aspetual em LP. Para cada um destes eixos, salientamos as seguintes conclusões: a) o contexto formal/ não formal é aquele que é considerado o mais eficaz; a apropriação da LP decorre ainda em contexto de autoaprendizagem e em contexto informal. A expressão oral afigura-se como uma competência de intervenção prioritária para este público. b) os repertórios linguísticos dos informantes deste estudo são limitados em número e diversidade de línguas, estando quase circunscritos às línguas eslavas, com amplo destaque para o Russo. A influência das Línguas Maternas na apropriação da LP é percecionada, de uma forma geral, como negativa, e é reduzida a adoção de estratégias de rentabilização interlinguística. c) as principais dificuldades no que se refere ao Tempo e Aspeto prendem- -se com o modo conjuntivo, os tempos compostos, os valores secundários de alguns tempos verbais, o pretérito perfeito composto do indicativo, a distinção entre o pretérito perfeito simples e o pretérito imperfeito do indicativo e a distinção entre os verbos ‘ser’ e ‘estar’. De uma forma global, apontam-se como pistas de intervenção a criação de cursos de LP de nível mais avançado, uma maior rentabilização do capital linguístico presente em sala de aula e a frequência, por parte dos docentes, de formação em línguas eslavas. A nível de recursos didáticos, sugere-se a elaboração de materiais bilingues para autoaprendizagem e de materiais de apoio ao professor. Seria igualmente útil a promoção de mais oportunidades de interação entre imigrantes e nativos.

A construção social da educação não-formal: novos paradigmas da sociedade do conhecimento - a competência como uma construção social

Disssertação de mest., Ciências da Educação e da Formação (Sociologia da Educação e da Formação), Faculdade de Ciências Humanas e Sociais, Univ. do Algarve, 2010