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An original family of multivalent vectors encompassing gemini and facial amphiphilicity, namely cationic Siamese twin surfactants, has been prepared fromthe disaccharide trehalose; molecular engineering lets us modulate the self-assembling properties and the topology of the nanocomplexes with plasmid DNA for efficient gene delivery in vitro and in vivo.

Poster apresentado no XXV Congresso da Ordem dos Médicos Dentistas. 10-12 Novembro 2016, Exponor, Matosinhos, Portugal N/A

This research work is devoted to the problem of excessive vertical vibrations that short to medium-span railway bridges may experiment due to resonance phenomena. A new alternative based on externally increasing the overall damping of the structure by retrofitting the deck with fluid-viscous dampers is proposed in order to reduce detrimental levels of transverse acceleration to admissible ones. This solution could substitute a classical strengthening process or even the complete demolition and replacement of the deck in existing structures under new traffic requirements such as an increase in the speed of the line. A particular configuration of the retrofitting system is proposed which allows the transformation of the vertical oscillations that the deck experiments under the circulation of the railway vehicles into elongation rates of the devices, leading to energy dissipation and the subsequent reduction of the super-structure resonant response. The proposed system could be installed in the original structure and maintained without interfering with everyday traffic.

O bem-estar dos funcionários no ambiente de trabalho é fundamental para que estes procedam à realização das suas actividades, sem colocarem em risco o factor saúde. Este artigo incide na avaliação do factor de risco que é o ruído, englobando cinco postos de trabalho inseridos no bloco operatório do Hospital de S. Marcos, em Braga. O estudo debruça-se na análise do ruído, motivado pelo facto dos responsáveis do Departamento de Riscos do Hospital terem recebido queixas por parte dos colaboradores, após a adopção de medidas de protecção individual. Procede-se, desta forma, ao estudo do local de trabalho, em que se realiza a recolha de duas medições da pressão sonora, em datas e horas diferentes de forma a obter uma amostra mais representativa do funcionamento destes serviços. Na análise dos resultados, tendo em conta o valor limite de Exposição Pessoal Diária (87 dB (A)), permitido pela lei portuguesa (DR 182/2006), denotase a existência de não cumprimento do previsto neste diploma legal. O valor referido é ultrapassado pela utilização de uma pistola de ar comprimido na secagem do material. Sem alternativa de alteração do equipamento, será importante estudar as características dos protectores auditivos implementados, de forma a verificar se estes não influenciam a capacidade auditiva dos seus utilizadores e se os protegem da exposição a que estão sujeitos. Através de dados fornecidos pelo fabricante dos protectores auditivos verifica-se que estes são adequados aos níveis de ruído existentes, protegendo desta forma os utilizadores expostos ao ruído., The well-being of employees in the workplace is crucial to their ability to carry out their daily activities without putting at risk their health. The focal point of this article was the assessment workers noise exposure, in five workplaces including the operating room of the Hospital S. Marcos, Braga. It focuses on the analysis of noise exposure due to the existence of some complaints from workers who have to use personal protective equipments. Accordingly, the study included the assessment of noise exposure using two measurements of sound pressure level at different dates and times, in order to obtain a larger sample. In the analyses of the results, and taking into account the limits for Daily Personal Exposure (87 dB (A)) allowed by Portuguese law (DR 182/2006), it was possible to notice that the workers exposure is high than the defined in the legislation. It appears that this value is exceeded due to the use of a compressed air gun used for drying the material. With no other options to change the equipment, it is very important to study the characteristics of hearing protection devices, in order to check if the devices do not affect workers’ hearing ability and if they protect workers from noise exposure. Using data supplied by the manufacturer of hearing protectors it appears that these are appropriate to the considered noise levels, thereby protecting users exposed to noise., info:eu-repo/semantics/publishedVersion

An increasing number of pathologies have been linked to Toll-like receptor 4 (TLR4) activation and signaling, therefore new hit and lead compounds targeting this receptor activation process are urgently needed. We report on the synthesis and biological properties of glycolipids based on glucose and trehalose scaffolds which potently inhibit TLR4 activation and signaling in vitro and in vivo. Structure-activity relationship studies on these compounds indicate that the presence of fatty ester chains in the molecule is a primary prerequisite for biological activity and point to facial amphiphilicity as a preferred architecture for TLR4 antagonism. The cationic glycolipids here presented can be considered as new lead compounds for the development of drugs targeting TLR4 activation and signaling in infectious, inflammatory, and autoimmune diseases. Interestingly, the biological activity of the best drug candidate was retained after adsorption at the surface of colloidal gold nanoparticles, broadening the options for clinical development.