Exposure to airborne ultrafine particles from cooking in portuguese homes

Cooking was found to be a main source of submicrometer and ultrafine aerosols from gas combustion in stoves. Therefore, this study consisted of the determination of the alveolar deposited surface area due to aerosols resulting from common domestic cooking activities (boiling fish, vegetables, or pasta, and frying hamburgers and eggs). The concentration of ultrafine particles during the cooking events significantly increased from a baseline of 42.7 mu m(2)/cm(3) (increased to 72.9 mu m(2)/cm(3) due to gas burning) to a maximum of 890.3 mu m(2)/cm(3) measured during fish boiling in water, and a maximum of 4500 mu m(2)/cm(3) during meat frying. This clearly shows that a domestic activity such as cooking can lead to exposures as high as those of occupational exposure activities

Chemical modification strategies to prepare advanced protein-based biomaterials

Nature is a superb source of inspiration when it comes to the development of biomaterials. Proteins, an exquisite asset virtually involved in all biological functions, are envisioned as a biomaterial due to their ability to be chemically modified. Owing to the rich chemical repertoire provided by the side chains and C-/N-terminus present in their backbone, scientists are pursuing chemical ways to upgrade isolated proteins, while maintaining their biological activity or relevant structural properties. By inserting chemical motifs, the crosslinking capability of proteins and capability to attach biochemical and molecular groups can be controlled yielding nano to macro constructs and hydrogels with improved physicochemical and mechanical properties. These cutting-edge approaches elevate the potential use of proteins as promising biomaterials for biotechnology and biomedicine.publishe

Layer-by-Layer Deposition of Antibacterial Polyelectrolytes on Cotton Fibres

The introduction of molecules with biological properties on textile materials is essential for a number of biotechnological applications. With the purpose of testing new processes applied to textiles, in this study, we present the first results on the feasibility of using the Layerby-Layer (LbL) deposition process in natural fibers such as cotton, with natural polyelectrolytes like chitosan (CH) and alginic acid sodium salt (ALG), the durability of CH/ALG multilayer on cotton were evaluated. The increase of negative charges to the substrate cotton was made with NaBr and TEMPO, to ensure the success of the process of LbL. Three characterization methods to assess electrostatic LbL deposition were performed: the contact angle between a liquid (water) and the sample surface, in order to characterize the wettability of the samples with the different layers of CH and ALG; dyeing of the CH/ALG assembled cotton fabric with cationic methylene blue that shows regular changes in terms of color depth (K/S value), which indicate that the surface were alternately deposited with CH and ALG layers and, finally, the analysis by infrared spectroscopy using Fourier Transform with Attenuated Total Reflection (ATR-FTIR), to assess the changes in the interaction between CH and ALG deposited on cotton samples.info:eu-repo/semantics/publishedVersio

Layer-by-layer deposition of antimicrobial polymers on cellulosic fibers: a new strategy to develop bioactive textiles

In recent years, there has been an increase of infectious diseases caused by different microorganisms and the development of antibiotic resistance. In this way, the search for new and efficient antibacterial materials is imperative. The main polysaccharides currently used in the biomedical and pharmaceutical domains are chitin and its derivative chitosan (CH) and alginates (ALG). In this study, a simple technique of Layer by Layer (LbL) of applying polycation CH and polyanion ALG was used to prepare CH/ALG multilayers on cotton samples via the electrostatic assembly with success. The CH/ALG cotton samples (functionalized) were investigated for their antibacterial properties towards Staphylococcus aureus and Klebsiella pneumonia using the international standard method JIS L 1902:2002. The antibacterial activity of the functionalized samples was tested in terms of bacteriostatic and bactericidal activity, and results showed that the samples exhibited a bacteriostatic effect on the two bacteria tested, as expected. In addition, samples with five layers (CH/ALG/CH/ALG/CH) were more effective in inhibiting bacterial growth. This new coating for cellulosic fibers is a new strategy and may open new avenues for the development of antimicrobial polymers with potential application in health-care field.info:eu-repo/semantics/publishedVersio

Taas – ticketing as a service

The goal of this research work is to introduce the concept of a lower cost flexible system for ticketing purposes implemented on a cloud platform. We propose therefore the evolution of the traditional architecture of ticketing for a cloud based architecture in which the core processes of ticketing are offered through a Software-as-a-Service (SaaS) business model, which can be subscribed by operators that pay-per-use. Ticketing terminal equipment (e.g. gates, validators, vending machines) are integrated in the cloud environment. This approach is achieved by moving business logic from terminals to the cloud. Each terminal is registered to be managed by each own operator, configuring a multi-tenant implementation which is vendor hardware independent, allowing to address elasticity and interoperability issues. The elasticity of the cloud will support the expansion/implosion of small (transport) operators business around electronic ticketing. In the near future, this ticketing solution will promote collaboration between transport operators

Descriptive analysis of tantalum paragenesis and tantalum pegmatites from the South Pegmatite District of Zambezian Province (Mozambique)

The differences between NYF and LCT pegmatite evolution and regional distribution in Zambézia Pegmatite Province are the main determinants of its tantalum potentiality. Alto Ligonha District in Central Zambézia holds important Ta resources in relation to LCT giant pegmatites, which have been mined for decades and are reasonably known. Minor attention was dedicated since now to the South District. Recent studies dedicated to this domain revealed several pegmatite fields with a great diversity of Ta mineralization: M´Luma – Nicula - low Ta NYF pegmatites, with high Sc, Y, Ti, R.E. and ixiolite-cheralite dominant ores; Rio Licungo - low Ta NYF and beryl pegmatites, with high Bi, W and struverite dominant ores; Rio Namivo - low to high Ta NYF to LCT pegmatites, beryl rich with petalite and spodumene as high temperature remnants and tantalite-tapiolite-microlite dominant ores. Regional distribution and paragenetic analysis of some key pegmatites suggest that South District reveals a more proximal and sub-autochthonous emplacement of the pegmatite bodies in tangential ruptures under the cover terrenes of Mamala to Morrua Formations, which undergone a different evolution since Pan-African event to uplifting an exhumation. In what concerns the strategic stage of exploration, such a pattern of emplacement and evolution, suggests the possibility of future detection of unknown high Ta pegmatites at the South District

Assessment of exposure to airborne ultrafine particles in the urban environment of Lisbon, Portugal

The aim of this study was the assessment of exposure to ultrafine in the urban environment of Lisbon, Portugal, due to automobile traffic, and consisted of the determination of deposited alveolar surface area in an avenue leading to the town center during late spring. This study revealed differentiated patterns for weekdays and weekends, which could be related with the fluxes of automobile traffic. During a typical week, ultrafine particles alveolar deposited surface area varied between 35.0 and 89.2 μm2/cm3, which is comparable with levels reported for other towns such in Germany and the United States. These measurements were also complemented by measuring the electrical mobility diameter (varying from 18.3 to 128.3 nm) and number of particles that showed higher values than those previously reported for Madrid and Brisbane. Also, electron microscopy showed that the collected particles were composed of carbonaceous agglomerates, typical of particles emitted by the exhaustion of diesel vehicles. Implications: The approach of this study considers the measurement of surface deposited alveolar area of particles in the outdoor urban environment of Lisbon, Portugal. This type of measurements has not been done so far. Only particulate matter with aerodynamic diameters 10 (PM10) μm have been measured in outdoor environments and the levels found cannot be found responsible for all the observed health effects. Therefore, the exposure to nano- and ultrafine particles has not been assessed systematically, and several authors consider this as a real knowledge gap and claim for data such as these that will allow for deriving better and more comprehensive epidemiologic studies. Nanoparticle surface area monitor (NSAM) equipments are recent ones and their use has been limited to indoor atmospheres. However, as this study shows, NSAM is a very powerful tool for outdoor environments also. As most lung diseases are, in fact, related to deposition of the alveolar region of the lung, the metric used in this study is the ideal one

Oxidative DNA damage protection and repair by polyphenolic compounds in PC12 cells

Biological systems are frequently exposed to excessive reactive oxygen species, causing a disturbance in the cells natural antioxidant defence systems and resulting in damage to all biomolecules, including nucleic acids. In fact, oxidative DNA damage is described as the type of damage most likely to occur in neuronal cells. In this study, three polyphenolic compounds, luteolin, quercetin and rosmarinic acid, were investigated for their protective effects against oxidative DNA damage induced in PC12 cells, a neuronal cell model. Although luteolin and quercetin prevented the formation of strand breaks to a greater extent than rosmarinic acid, this last one presented the highest capacity to repair strand breaks formation. In addition, rosmarinic acid was the only compound tested that increased the repair of oxidized nucleotidic bases induced with the photosensitizer compound [R]-1-[(10-chloro-4-oxo-3-phenyl-4H-benzo[a]quinolizin-1-yl) carbonyl]-2-pyrrolidine- methanol (Ro 19-8022). The activity of repair enzymes was indicated by the in vitro base excision repair assay, using a cell-free extract obtained from cells previously treated with the compounds to incise DNA. The protective effect of rosmarinic acid was further confirmed by the increased expression of OGG1 repair gene, observed through real time RT-PCR. The data obtained is indicative that rosmarinic acid seems to act on the intracellular mechanisms responsible for DNA repair, rather than by a direct effect on reactive oxygen species scavenging, as deducted from the effects observed for luteolin and quercetin. Therefore, these results suggest the importance of these polyphenols, and in particular rosmarinic acid, as protectors of oxidative stress-induced DNA damage that commonly occurs in several pathological conditions, such as neurodegenerative diseases.Fundação para a Ciência e a Tecnologia (FCT) - bolsa SFRH/BD/17174/2004

O que é ser criança? Da genética ao comportamento

Este artigo foi originalmente publicado em Novos Desafios à Bioética, Porto Editora, 2001. Foi reeditado, neste número especial de Análise Psicológica, com as devidas autorizações.Cada gene só se pode exprimir em função do modo como cada fase ambiental da evolução humana modela a força potencial da natureza. A expressão genómica com todas as suas influências é, de facto, condicionada pelas sucessivas interacções entre o que é potencial e o que são os sucessivos ambientes que constituem o envelope do biológico, desde o núcleo ao citoplasma, desde a célula ao tecido, desde o órgão ao corpo total, desde o corpo à relação com o outro mais significativo nos primeiros tempos de vida e que é a mãe, até às outras todas relações sociais com os outros mais ou menos preferenciais que a família e a sociedade vão proporcionando, nas sucessivas etapas do ciclo da vida. O mito determinista que tanto nos legou em termos de significado nas primeiras relações, cruza-se com as outras realidades influenciais através das quais sabemos que nunca nada está perdido em função da extraordinária capacidade de adaptação humana em todos as fases potenciais da vida. O modelo etológico ter-nos-á influenciado a pensar em termos de sobrevivência quando caracteriza a evolução em termos de competência de espécies na mira de garantir aquela mesma sobrevivência. Porém, a caracterização da espécie humana vai no sentido de uma evolução complexa destinada a garantir competências susceptíveis de condicionar capacidades decisivas como são as de constituir família e de cooperar em grupos sociais com objectivos comuns, cada vez mais complexos. Ser Criança significa o destino de vida feita relação e afecto.Each gene can only express itself according to the way in which each environmental phase of human evolution configures the potential force of nature. Genomic expression and its influences is conditioned by the successive interactions between what is potential and the successive environments that constitute the biological envelope, from the nucleus to the cytoplasm, from the cell to the tissue, from the organ to the total body, from the body to the relationship with the meaningful other during the first years of life, which is the mother, and all the other social relationships with members of the family and society, in the several stages of the life cycle. The determinist myth that left us so much in terms of the meaning of the first relationships intersects with the other influential realities which show that nothing is ever lost, due to the extraordinary human capacity for adaptation in all the potential phases of life. The ethological model has influenced us to think in terms of survival by characterising evolution as species’ competences to guarantee survival. However, the characterisation of the human species is based on the idea of a complex evolution, aimed at guaranteeing the competences and skills needed to create families and cooperate in social groups with common goals, which are more and more complex.info:eu-repo/semantics/publishedVersio