Hacia un nuevo paradigma historiográfico

On the basis of understanding the «Crisis of history» both like difficulty and mutation, the author analyzes its genesis from the 1970s, and how historians are going out of the crisis changing the historiographics paradigms (This does not mean that they value all those changes as positive ones). Carlos Barros understands «paradigms», according to Kuhn, as the values shared by the historians community. The article also studies the challenges that globalization, new technologies, its relationship with society and contemporary science pose to the new historiographic paradigm under construction.Sobre la base de entender simultáneamente la «crisis de la historia» como dificultad y mutación, el autor analiza su génesis desde los años 1970s, y cómo los historiadores están saliendo de ella cambiando de paradigmas historiográficos. Sin que ello quiera decir que se valoren sin más como buenos todas los cambios en marcha. Entendiendo por «paradigma», según Kuhn, los valores compartidos por la comunidad de historiadores. Se estudian asimismo los retos que la globalización, las nuevas tecnologías, la relación con la sociedad y la ciencia contemporáneas, plantean al nuevo paradigma historiográfico en construcción

Oil Prices: Persistence and Breaks

The rise of oil prices is a main issue in contemporary economics. This study examines the monthly, weekly and daily structure in several oil prices series using a modeling approach based on fractional integration and long range dependence. The results indicate that oil prices series are highly persistent, with orders of integration equal to or higher than 1. Breaks in the series do not alter the main conclusions of this study. That means that shocks have a permanent nature and strong policy measures must be implemented to return the series to their original long term projections

Salt weathering of limestones: susceptibility of petrographical features (SEM study)

Fundação para a Ciência e a Tecnologia (FCT) - Verbas nacionais e FEDE

Housing Sales in Urban Beijing

In the housing market, new properties sometimes experience delays before they are sold. Such delays reflect the preferences of buyers in respect of the homes’ characteristics. Therefore, it is important for managerial purposes to identify the causes of housing sales delays. After analyzing the delays in sales of housing in Beijing City, China, the principal finding of this study is that delays are largely explained by the dwellings’ characteristics and location. Policy implications of the research findings, particularly those related to means of reducing the delays, are discussed

Performance of stones under different conditions : a study of metro stations

The study of stone alterations in the Lisbon Metro stations allowed the discussion of the influence in the development of these alterations of stones characteristics and the actual conditions to which the stones are subjected. Alterations occur under what can be considered the usual conditions of use but also under abnormal situations that must be taken into account given its frequency. The diverse situations identified are considered in the discussion of possible recommendations bearing in mind the actual situations found at the stations.Financiado pela Fundação para a Ciência e a Tecnologia com fundos nacionais (programa plurianual de financiamento de unidades de investigação)

Performance of stones under different conditions: a study of metro stations

Fundação para a Ciência e a Tecnologia (FCT

Natural extracts from wild flowers used in Portuguese folk medicine like a new antifungal agents against Candida species

The prevalence of opportunistic fungal infections has been increasing dramatically over the recent decades mainly due to the boom of the AIDS epidemic, increasing number of immunocompromised patients and the commonly use of indwelling medical devices. Although Candida albicans has been regarded as the most common causative agent of fungal infection in humans, nowadays other non-Candida albicans Candida (NCAC) species such as Candida glabrata, Candida tropicalis and Candida parapsilosis, are emerging as significant nosocomial pathogens and with high level of resistance to certain antifungal drugs. So, in the last years the interest in natural compounds has raised, specifically some phenolic extracts which have been known in folk medicine as antimicrobial agents. Thus, this work aimed to perform a screening of the antifungal potential of phenolic extracts of Castanea sativa, Filipendula ulmaria and Rosa micrantha flowers from Northeastern Portugal, against Candida species. The extracts were exhaustively characterized by HPLC-DAD-ESI/MS. Hydrolysable tannins were the main group of phenolic compounds in C. sativa and F. ulmaria samples, while flavonoids including procyanidins were the most abundant group in R. micrantha (6090 ± 253 mg/Kg). The minimal inhibitory concentration (MIC) was determined according with the guidelines in National Committee for Clinical Laboratory Standards (NCCLS, M27-A2 document) with some modifications. All extracts revealed promising antifungal effect, with MIC values ranging from concentrations under 0.05 to 0.625 mg/ml. R. micrantha extract showed a strong effect (MIC ≤ 0.155mg/ml) against the four strains assayed. Furthermore, it is also possible to assume that was against C. glabrata and C. parapsilosis that the phenolic extracts showed the highest activity (MIC <0.05mg/ml). Finally, the natural extracts effect was assessed on biofilm formation and on pre-formed biofilms by total biomass quantification using CV staining (1%, v/v). F. ulmaria and R. Micrantha were causative agent of important inhibition and destruction of C. tropicalis biofilms. In summary, the significant antifungal activity of C. sativa, F. ulmaria and R. micrantha revealed in this work, suggest that they could serve as a source of compounds with therapeutic potential against Candida-related infections

Characterization and strengthening a "ghost" building

In the middle of the eighties it was intended to build a one family dwelling at a North Portuguese Region, but a much bigger edification was constructed, without any design elements. At the end of the nineties this construction was acquired, and another architectonic and functional configuration was designed for this space. Since there were not any elements available for the existent construction, it was carried out several strategies for its geometrical, structural and material characterization. These elements gave the indispensable information for analysing the structural stability of the building, which revealed to be necessary to strengthen foundations, beams and columns. The procedures for characterizing the construction, the structural stability analysis and the strengthening strategies are described in the work