Técnica de Preparação Biologicamente Orientada (BOPT)

As técnicas de preparação dentária protética mudaram rapidamente nos últimos anos para satisfazer o aspecto estético que o paciente solicita, exigindo um maior conhecimento dos diferentes métodos de preparação. As técnicas convencionais, caracterizam-se por coroas adaptadas à margem gengival do paciente ao contrário da técnica de preparação biologicamente orientada (BOPT) caracterizada por guiar periodontalmente os tecidos. Como objetivo, será realizada uma análise comparativa de técnicas tradicionais para preparações dentárias com uma linha de terminação e a técnica de preparação biologicamente orientada (BOPT) sem uma linha de terminação definida. A elaboração de uma investigação qualitativa combina estas técnicas com outras tradicionalmente aplicadas com uma linha de acabamento horizontal. Quanto à metodologia, foi realizada uma investigação documental através de uma revisão sistemática nas plataformas académicas, com o objetivo: de rever aspetos conceptuais das técnicas tradicionais e a técnica BOPT; estudar protocolos de aplicação específicos e analisar a diversidade de abordagens consideradas em termos de estudos de caso. No total de 30 fontes documentais consultadas, baseadas nos critérios de inclusão e exclusão, apenas 25 foram selecionadas. Quanto aos resultados da investigação, considerámos a exposição das vantagens de cada técnica na aplicação dos tratamentos, para verificar os aspetos positivos e negativos que ilustram as possibilidades que representam nos tratamentos atuais

Evolutionary dynamics of the cryptocurrency market

The cryptocurrency market surpassed the barrier of $100 billion market capitalization in June 2017, after months of steady growth. Despite its increasing relevance in the financial world, a comprehensive analysis of the whole system is still lacking, as most studies have focused exclusively on the behaviour of one (Bitcoin) or few cryptocurrencies. Here, we consider the history of the entire market and analyse the behaviour of 1469 cryptocurrencies introduced between April 2013 and May 2017. We reveal that, while new cryptocurrencies appear and disappear continuously and their market capitalization is increasing (super-)exponentially, several statistical properties of the market have been stable for years. These include the number of active cryptocurrencies, market share distribution and the turnover of cryptocurrencies. Adopting an ecological perspective, we show that the so-called neutral model of evolution is able to reproduce a number of key empirical observations, despite its simplicity and the assumption of no selective advantage of one cryptocurrency over another. Our results shed light on the properties of the cryptocurrency market and establish a first formal link between ecological modelling and the study of this growing system. We anticipate they will spark further research in this direction

Simple Nudges for Better Password Creation

Recent security breaches have highlighted the consequences of reusing passwords across online accounts. Recent guidance on password policies by the UK government recommend an emphasis on password length over an extended character set for generating secure but memorable passwords without cognitive overload. This paper explores the role of three nudges in creating website-specific passwords: financial incentive (present vs absent), length instruction (long password vs no instruction) and stimulus (picture present vs not present). Mechanical Turk workers were asked to create a password in one of these conditions and the resulting passwords were evaluated based on character length, resistance to automated guessing attacks, and time taken to create the password. We found that users created longer passwords when asked to do so or when given a financial incentive and these longer passwords were harder to guess than passwords created with no instruction. Using a picture nudge to support password creation did not lead to passwords that were either longer or more resistant to attacks but did lead to account-specific passwords

Compendio de geografía universal redactado bajo un nuevo plan a fin de facilitar su estudio y adaptarse a la edad y capacidad de todos los jóvenes

Donación J.L. Estrada (Biblioteca General)Digitalizada en formato pd