Bioactive nanocomposite spheres with proved shape memory capability in bone defects

Bioactive glass nanoparticles (BGNPs) promote an apatite surface layer in physiologic conditions that lead to a good interfacial bonding with bone.1 A strategy to induce bioactivity in non-bioactive polymeric biomaterials is to incorporate BGNPs in the polymer matrix. This combination creates a nanocomposite material with increased osteoconductive properties. Chitosan (CHT) is a polymer obtained by deacetylation of chitin and is biodegradable, non-toxic and biocompatible. The combination of CHT and the BGNPs aims at designing biocompatible spheres promoting the formation of a calcium phosphate layer at the nanocomposite surface, thus enhancing the osteoconductivity behaviour of the biomaterial. Shape memory polymers (SMP) are stimuli-responsive materials that offer mechanical and geometrical action triggered by an external stimulus.2 They can be deformed and fixed into a temporary shape which remains stable unless exposed to a proper stimulus that triggers recovery of their original shape. This advanced functionality makes such SMPs suitable to be implanted using minimally invasive surgery procedures. Regarding that, the inclusion of therapeutic molecules becomes attractive.�� We propose the synthesis of shape memory bioactive nanocomposite spheres with drug release capability.3 �� 1.�� L. L. Hench, Am. Ceram. Soc. Bull., 1993, 72, 93-98. 2.�� A. Lendlein and S. Kelch, Angew Chem Int Edit, 2002, 41, 2034-2057. 3.�� �� . J. Leite, S. G. Caridade and J. F. Mano, Journal of Non-Crystalline Solids (in Press)

Princ��pios para a reabilita����o sustent��vel low cost de edif��cios antigos: estudo de um quarteir��o no centro da cidade do Porto

Disserta����o de mestrado em Constru����o e Reabilita����o Sustent��vel

Effector memory CD4+ T cells are associated with cognitive performance in a senior population

Objective: Immunosenescence and cognitive decline are common markers of the aging process. Taking into consideration the heterogeneity observed in aging processes and the recently described link between lymphocytes and cognition, we herein explored the possibility of an association between alterations in lymphocytic populations and cognitive performance. Methods: In a cohort of cognitively healthy adults (n = 114), previously characterized by diverse neurocognitive/psychological performance patterns, detailed peripheral blood immunophenotyping of both the innate and adaptive immune systems was performed by flow cytometry. Results: Better cognitive performance was associated with lower numbers of effector memory CD4(+) T cells and higher numbers of naive CD8(+) T cells and B cells. Furthermore, effector memory CD4(+) T cells were found to be predictors of general and executive function and memory, even when factors known to influence cognitive performance in older individuals (e.g., age, sex, education, and mood) were taken into account. Conclusions: This is the first study in humans associating specific phenotypes of the immune system with distinct cognitive performance in healthy aging.

Roteiro metodol��gico para o estudo dos moinhos e aproveitamentos hidr��ulicos no concelho de Lousada

A Ag��ncia Portuguesa do Ambiente �� possuidora de um valioso arquivo, resultante da atividade centen��ria desenvolvida pelos diferentes organismos com tutela sobre a gest��o da ��gua e o planeamento dos recursos h��dricos, que importa conhecer e divulgar. O Arquivo Hist��rico dos Servi��os Hidr��ulicos �� um dos mais ricos acervos locais do Pa��s, reunindo um conjunto de milhares de documentos, que v��o do s��culo XIX �� atualidade, constituindo um reposit��rio documental com caracter��sticas ��mpares e um testemunho da identidade, mem��ria e hist��ria dos Servi��os Hidr��ulicos. Os processos arquivados contam casos de estudo que percorrem os usos das ��guas p��blicas para diferentes fins e as modalidades da sua utiliza����o, das quais queremos destacar os aproveitamentos hidr��ulicos e a labora����o de moinhos. Com este artigo, pretendemos apresentar um roteiro metodol��gico para o estudo das formas de organiza����o dos processos existentes no arquivo sobre os moinhos e aproveitamentos hidr��ulicos, no concelho de Lousada, no que respeita aos documentos e pe��as anexas, bem como aos modelos administrativos subjacentes.

Ensaios sobre a responsabilidade social corporativa e sua divulga����o no setor portu��rio

Tese de Doutoramento em Contabilidade

Off-line simulation inspires insight: a neurodynamics approach to efficient robot task learning

There is currently an increasing demand for robots able to acquire the sequential organization of tasks from social learning interactions with ordinary people. Interactive learning-by-demonstration and communication is a promising research topic in current robotics research. However, the efficient acquisition of generalized task representations that allow the robot to adapt to different users and contexts is a major challenge. In this paper, we present a dynamic neural field (DNF) model that is inspired by the hypothesis that the nervous system uses the off-line re-activation of initial memory traces to incrementally incorporate new information into structured knowledge. To achieve this, the model combines fast activation-based learning to robustly represent sequential information from single task demonstrations with slower, weight-based learning during internal simulations to establish longer-term associations between neural populations representing individual subtasks. The efficiency of the learning process is tested in an assembly paradigm in which the humanoid robot ARoS learns to construct a toy vehicle from its parts. User demonstrations with different serial orders together with the correction of initial prediction errors allow the robot to acquire generalized task knowledge about possible serial orders and the longer term dependencies between subgoals in very few social learning interactions. This success is shown in a joint action scenario in which ARoS uses the newly acquired assembly plan to construct the toy together with a human partner.

As disfun����es da mem��ria organizacional e suas implica����es no uso dos sistemas de informa����o: um caso de estudo

Disserta����o de mestrado integrado em Engenharia e Gest��o de Sistemas de Informa����o

O papel da diplomacia econ��mica na dinamiza����o da economia: o caso de Cabo Verde

Disserta����o de mestrado em Neg��cios Internacionais

O filme ���A Gaiola Dourada���: reflex��es sobre o regresso em for��a da emigra����o portuguesa e a ���portugalidade��� de uma gaiola (cada vez menos) dourada

A hist��ria de um casal de emigrantes portugueses em Fran��a bateu, no ver��o de 2013, recordes de audi��ncia nas salas de cinema. O filme ���A Gaiola Dourada���, de Ruben Alves, recuperou a tem��tica da emigra����o portuguesa, numa altura em que esta atingiu o boom registado nos anos 1960. Recorrendo ao seu percurso, o realizador refere-se �� ���portugalidade��� como alegada ���perten��a a Portugal���, que assume como um clich��, e utiliza de forma humor��stica v��rios estere��tipos associados aos emigrantes portugueses, atrav��s dos quais �� mostrada alguma vergonha que os filhos dos emigrantes sentem em rela����o ao comportamento dos pais, trazendo ao de cima os contrastes com a sociedade onde vivem. A grande fic����o reside no regresso ao pa��s de origem, concretizando o sonho da grande maioria dos emigrantes, mas subvertendo a l��gica: no filme, n��o s��o os pais que voltam a Portugal, mas os filhos, que aparentemente pouco se identificam com o pa��s dos progenitores. ���A Gaiola Dourada��� reintroduziu o debate sobre a emigra����o em Portugal, aproveitando a crise econ��mica para refletir sobre o seu regresso em for��a, bem como tra��ar o perfil dos novos emigrantes. Ser�� que os portugueses na ���di��spora��� ainda reavivam a chama ���lusitana��� (Gon��alves, 2009)? E ser�� que a partilha do nome ���Portugal��� basta para sublinhar uma alegada identidade nacional (Sobral, 2012)?