Hybrid Nanocomposites Produced by Sputtering: Interaction with Eukaryotic and Prokaryotic Cells

The use of composite materials for different and diverse technological applications is a growing field. The development of this class of materials arises when it is required from a material a combination of properties that are impossible to co-exist, such as, for example, high hardness and good tenacity. However, in some applications the main focus of this combination of characteristics/properties is only required at the material surface; in this cases, the composite will be deposited onto the surface as a coating. Moreover, the introduction of reinforcements of nanometric size, where one of the dimensions is lower than 100 nm, may induce, in the deposited composite, particularly appealing properties due to the nanometric scale. This chapter presents the use of a particular deposition technique—sputtering—for the production of nanocomposites made of dissimilar materials such as ceramic/metal, ceramic/polymer and ceramic/polymer/metal. The application of these surfaces in interaction with both eukaryotic and prokaryotic cells will be given as an example of the broad range of applications of the developed surfaces

Redes agroalimentares alternativas e suas implicações para a política social: as motivações dos consumidores das Comunidades que Sustentam a Agricultura no Brasil

Dissertação de Mestrado em Política SocialEste trabalho abordará a Comunidade que Sustenta a Agricultura – CSA, tecnologia social em que consumidores tornam-se coagricultores ao financiarem a produção de um agricultor local, compartilhando os riscos da produção de alimentos limpos. O objetivo da pesquisa é compreender as motivações dos consumidores ao aderirem a CSA e as implicações dessa participação para as políticas sociais. Utilizando-se de métodos qualitativos, foram realizadas 11 entrevistas semiestruturadas com coagricultores participantes de CSAs de Brasília/DF por meio de plataformas digitais. Os resultados indicam que iniciativas alternativas ligadas ao consumo e produção de bens alimentares podem criar mercados mais justos, impactar diretamente na segurança alimentar e nutricional – SAN da comunidade e atuar como um movimento de resistência ao modo convencional de produção e acesso a alimentos. Também contribuem para o desenvolvimento sustentável ao atenderem às particularidades de cada território, fortalecendo a comunidade. Ainda é necessário, entretanto, ampliar o acesso as CSAs, tornando a participação mais heterogênea. As redes agroalimentares alternativas possuem implicações para as políticas sociais ao promoverem o desenvolvimento rural, o fortalecimento da agricultura familiar, a preservação do ambiente e, sobretudo ao contribuírem para a saúde e para a SAN. Essas redes devem ser consideradas pelos governos como uma sinalização da sociedade para adoção de uma abordagem ecológica das políticas sociais. Por possuírem potencial para enfrentar os novos desafios de SAN do Brasil e indicarem soluções para a demanda ambiental do mundo atual, o Estado deve estar atento ao papel de governança dessas redes e ampliar o diálogo por meio de instâncias participativas da sociedade civil afim de absorver demandas e iniciativas.This work will address the Community Supported Agriculture - CSA, social technology in which consumers financing a local farmer production, sharing the risks of clean food production. The objective of this research is to understand the motivations of consumers to join the CSA and the implications of this participation for social policies. Using qualitative methods, 11 semistructured interviews were conducted with consumers participating in CSAs in Brasília/DF through digital platforms. The results indicate that alternative initiatives related to food consumption and production can create fairer markets, directly impact on food and nutritional security of the community and act as a resistance movement to the conventional way of production and access to food. They also contribute to sustainable development by addressing the particularities of each territory, strengthening the community . It is still necessary, however, to increase access to CSAs, making participation more heterogeneous. Alternative agrifood networks have implications for social policies by promoting rural development, strengthening family farming, preserving the environment and contributing to health and food security. These networks should be considered by governments as a sign of society for adopting an ecological approach to social policies. Because they have the potential to face the new challenges of food security in Brazil and indicate solutions for the environmental demand of the today’s world, the State must be attentive to the governance role of these networks and broaden the dialogue through participatory instances of civil society in order to absorb demands and initiatives.N/

Thin Films for Medical and Environmental Applications

A material that presents both the appropriate set of bulk properties in conjunction with an optimal surface performance is hardly found. For this reason, there is the need of modifying its surface. This is a standard procedure in many application fields but particularly important in the medical and environmental research. In this chapter, we describe the use of sputtering, as the chosen technology for the deposition of thin films. The use of the modified surfaces in the medical and environmental fields will be highlighted by two case studies in each one. In biomedicine, the surface modification of medical invasive devices for orthopedic and neural applications will be presented. For the environmental aspect, the results of two bioremediation tools, for arsenic and uranium removal, based on the immobilization of bacterial cells will be discussed

Influence of Au on antibacterial activity of Ag-TiCN coatings

The increasing demand for sustainable products requires the development of new knowledge-based materials with advanced properties. These products are then expected to: last longer, have a better performance, be safe, and be more efficient. These requirements, gain particular importance when dealing with applications involving the human body: the so-called biomaterials. Thus, the main aim of these investigations is to contribute to the development of new biomaterials that are able to prevent biofilm formation, since those complex microbial communities are responsible for the undesired reactions such as inflammation and infection, and consequently medical devices rejection. This work reports the development of Ag-TiCN coatings doped with gold. One series of samples was prepared by DC reactive magnetron sputtering using two targets, Ti and Ti+Ag, in an Ar + C2H2 + N2 atmosphere. Silver pellets were placed in the erosion area of Ti target in order to obtain a silver content up to 10 at. %. A second series of samples was deposited with the same conditions but with the Ti target doped with one Au piece. Extended physical, chemical and structural characterization such as the study of composition, grain size and texture phase evolution, phase composition, film surface topography and morphology, will be achieved resorting to surface analysis techniques, such as, Electron Probe Microanalysis (EPMA), X-ray diffraction (XRD), Atomic Force Microscopy (AFM), scanning electron microscopy (SEM-EDS). The galvanic couple formed between gold and silver, accelerates silver ion release and should provide more pronounced antibacterial activity. Staphylococcus epidermidis was selected to study coatings' antibacterial activity, and fibroblasts were used to test the cytotoxicity. Bacteria adhesion and biofilm formation on coatings were assessed by crystal violet staining, which quantifies total amount of biomass. Animal cell (fibroblasts) death was determined by MTS assay

Influence of albumin on the tribological behavior of Ag-Ti (C, N) thin films for orthopedic implants

With the increase of elderly population and the health problems arising nowadays, such as cancer, knee and hip joint prostheses are widely used worldwide. It is estimated that 20% of hip replacement surgeries simply fail after 5 years, due to wear loosening, instability and infection. In this paper it is reported the study of advanced materials with the ability to overcome some of these drawbacks. The development of ceramic coatings, based on carbonitrides of transition metals, such as TiCN, doped with silver, Ag, may represent an effective solution. Thin films of Ag-TiCN were produced by dc reactive magnetron sputtering with silver contents ranging from 4 to 8 at. %. The physical, chemical, structural, morphological/topographical, mechanical and tribological properties were evaluated. The tribological tests were performed in a unidirectional wear simulator, pin on disc, being the antagonists of a ceramic Al2O3 ball, and using simulate body fluids as lubricant. Hank’s Balanced Salt Solution (HBSS) and bovine serum albumin (BSA) in HBSS were chosen, in order to evaluate the lubrication ability of the solution containing the protein, albumin. The results revealed that the coatings with Ag content ranging from 4 to 8 at. %, were the most promising, as the tribological properties were superior to the results reported by other authors, which also developed Ag-TiCN coatings containing similar Ag contents and using similar test conditions. The presence of albumin lead to a lower wear in all the test conditions, and this enhancement was higher in the hydrophobic surfaces.This research is sponsored by FEDER funds through the program COMPETE - Programa Operacional Factores de Competitividade and by National funds through FCT - Fundacao para a Ciencia e a Tecnologia, in the framework of the Strategic Projects PEST-C/FIS/UI607/2011, and PEst-C/EME/UI0285/2011 and under the project, PTDC/CTM/102853/2008

An enzymatic route to a benzocarbazole framework using bacterial CotA laccase

The CotA laccase-catalysed oxidation of the meta, para-disubstituted arylamine 2,4-diaminophenyldiamine delivers, under mild reaction conditions, a benzocarbazole derivative (1) (74% yield), a key structural motif of a diverse range of applications. This work extends the scope of aromatic frameworks obtained using these enzymes and represents a new efficient and clean method to construct in one step C-C and C-N bonds

A imigração em Portugal na atualidade

A situação imigratória, seus efeitos económicos, sociais e identitários são um ponto de partida que condiciona o trabalho de animadores socioculturais em sua prática comunitária de desenvolvimento de uma convivência solidária. Eles não são condicionantes socioeconômicos, mas um ponto de partida para entender a dinâmica sociocultural e educacional de um trabalho multicultural no campo da animação sociocultural

Clinical education reflective ecological model for health science majors

The clinical education is an integral part of the Health Science majors’ curriculum programs of the University of Aveiro’s School of Health (i.e., Nursing, Physical Therapy, Radiology, Radiotherapy and Speech-Language Pathology) and aims to develop clinical competences in order to generate excellent health care professionals. The organization was based on the Ecological Model of Clinical-Reflective Training, which was characterized by inter-institutional interaction and student’s reflection on actions on a professional setting. This study encompassed two moments of clinical internships in the Nursing, Physical Therapy, Radiology and Radiotherapy majors. The Clinical Internship I provided the 123 students with a global view of the health care professional activities. The Clinical Internship II, with 119 students, developed competences of each health professional. Questionnaires with categorical scales from 1 to 5 evaluated the organization and efficiency of the two internships. The results revealed averages over 3 in all items. In conclusion, the Ecological Model of Clinical-Reflective Training was well accepted by students and clinical supervisors. Applications in the health care area were demonstrated

Biofilm formation, interaction and survival within A549 pneumocytes of Klebsiella pneumoniae clinical strains: identification of pulsotypes, multidrug-resistance and genes coding for adhesins: Formação de biofilme, interação e sobrevivência dentro dos pneumócitos A549 de cepas clínicas de Klebsiella pneumoniae: identificação de pulsótipos, multirresistência a drogas e codificação de genes para adesinas

Klebsiella pneumoniaehas become one of the major causes of hospital-acquired infections over decades due to the spread of virulent clones harboring resistant genes to multiple antimicrobial agents. The aim of this study was to investigate phenotypic and genotypic features of virulence mechanism expressed by K. pneumoniae clinical isolates of different PFGE types, including biofilm formation, interaction with pneumocytes A549 lineage and experimental infection by using C. elegans nematodes.  A total of 17 K. pneumoniae strains were isolated from different clinical specimens including blood, urine and respiratory infections. In this present study, 11 strains presented a varied multidrug-resistance profile harboring resistance genes coding for betalactams, aminoglicosydes, fluorquinolones and carbapenemases. PFGE analysis demonstrated the presence of four distinct pulsotypes among K. pneumoniae strains harboring virulence genes for siderophores and fimbiae type 1 and type 3. High adherence and biofilm formation were positively correlated for both polystyrene and glass surfaces in all K. pneumoniae strains analyzed. K. pneumoniae clinical strains showed the ability of adherence, internalization and persistence within human pulmonary epithelial A549 cell line, at different levels. Respiratory infections demonstrated a higher heterogeneity of PFGE types and levels of adherence, intracellular survival and persistence.K. pneumoniae strains were also submitted to Carnohabidits elegans in vivo infection model and data showed that after 24 hr almost 10% of urine-culture isolates worms were dead evidencing virulence profile. Notably, K. pneumoniae strains, presenting virulence genes, was significantly more virulent than those who did not presented any virulence gene after 5 days (survival >60% and >40%)