The mathematical description of the electrosynthesis of composites of oxy-hydroxycompounds cobalt with polypyrrole overooxidazed

The electrosynthesis of the composite with of the overoxidized polypyrrole with cobalt oxy-hydroxide in strongly acidic media has been described mathematically, using linear stability theory and bifurcation analysis. The steadystates stability conditions and oscillatory and monotonic instability requirements have been described too. The system´s behavior was compared with behavior of other systems with overoxidation, electropolymerization of heterocyclic compounds and electrosynthesis of the cobalt oxy-hydroxides

Antigenotoxicity of Ginkgo biloba extract in colonocytes

Plants have been used over centuries in traditional medicine for the treatment of human diseases. In the last decades the interest in medicinal plants has increased significantly owing to the antioxidant effect found in their natural extracts which is responsible for many therapeutic effects. The Ginkgo biloba leaf extract (GBE), widely used in traditional Chinese medicine, is nowadays intensively studied and sold all over the world due to its many health benefits, being used for the treatment of human pathologies such as neurodegenerative and cardiovascular diseases, and also to delay the ageing process. Although the antioxidant properties of GBE are well documented [1-3], studies on the antigenotoxic activity of GBE are still scarce. The colonic environment is continuously exposed to a large diversity of dietary compounds, some of them potentially carcinogenic, that may affect DNA integrity (e.g.: DNA oxidation and strand breaks) and alter cell genetic information, contributing to the development of colorectal cancer (CRC). Diets that are mainly composed of fruits and vegetables are rich in polyphenols and have been associated with CRC prevention [4]. Medicinal plant extracts may also be rich in polyphenols and can be used to prevent or reduce DNA damage. The chemical analysis of the ethanolic GBE allowed the identification of some G. biloba characteristic compounds, being mainly composed of one type of polyphenols designed as flavonoids, which are known for having strong antioxidant activity. Owing to this property, GBE could be a potential chemopreventive agent against CRC. Thus, GBE was subjected to simulated in vitro human digestion of the upper tract, originating a product (DGBE) that represents the extract when it reaches the colon during human digestion. GBE and DGBE demonstrated in vitro antioxidant activity and were tested in human colorectal adenocarcinoma cell line for their cytotoxicity (MTT assay) and antigenotoxicity (comet assay), where cells were pre-treated with each extract and subsequently challenged with H2O2. Both forms of the extract did not affect cell viability and decreased the level of DNA damage induced by oxidative stress. GBE and DGBE seem to be protecting DNA from damage, which could be the result of the stimulation of antioxidant defence mechanisms (such as the induction of antioxidant enzymatic activity or non-enzymatic defences) and DNA repair, or the extracts might be inducing moderate stress in cells, causing cell adaption when exposed to H2O2. Therefore, GBE shows a potential antigenotoxic effect, that seems to be retained after the digestive process, and might be the result of the antioxidant properties provided by the flavonoid fraction of the extract.This work is supported by: European Investment Funds by FEDER/COMPETE/POCI– Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT - Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013.info:eu-repo/semantics/publishedVersio

Eletrodos de SrTiO3 através de um novo método de precursores poliméricos.

Entrada padronizada: RIBEIRO, C

Dinâmica do estrato herbáceo de uma vegetação de caatinga do Sertão de Pernambuco sob intensidade de uso por caprinos.

Uma pastagem nativa de caatinga foi submetida a várias intesidades de uso (IU) por caprinos (1981-84), para verificar o efeito delas na degradação da vegetação. A pesquisa envolveu três lU variando de 1 cabra/1 ha para 1 cabra/3 ha, além da exclusão (sem pastejo), ocupando sete áreas variando de 15 a 45 ha. Usando-se quadrados de 1 m2, avaliou-se o efeito das lU sobre o estrato herbáceo, e não se detectou influência sobre a frequência das espécies herbáceas e nem sobre a densidade das plantas novas (altura < 0,5 m) das espécies lenhosas, cuja média no período foi de 2,401 plantas/m2, excluindo as plantas novas da árvore "Tabebuia spongiosa" Rizzini. Entre as 31 espécies herbáceas avaliadas, as frequências de 29 delas foram influenciadas (P<0,05) pela precipitação. "Selaginella convoluta" Spring e "Herissantia crispa" (L.) Briz., com frequências médias de 49,9 e 24,7%, respectivamente, não foram influenciadas pela precipitação. A densidade das plantas novas das espécies lenhosas também foi influenciada (P<0,05) pela precipitação, sendo a densidade em 1984 (3,005 plantas/m2) superior às densidades de 1982 e 1983 (1 ,895 e 2,055 plantas/m2, respectivamente). Em conclusão, altas lU por caprinos durante três anos não foram suficientes para causar degradação do estrato herbáceo da Caatinga. Precipitação foi o fator mais importante

Opportunities for mainstreaming biodiversity for food and nutrition into institutional food procurement programs in Brazil

Brazil has a well-established political and regulatory framework aimed at promoting food and nutritional security. This framework represents an innovative and ethical social contract aimed at achieving social inclusion, sustainable livelihoods and citizenship. It includes the Food Acquisition Program (PAA) and the National School Meals Program (PNAE), institutional food procurement programs which provide equitable support to family farming by acquiring their products at a fair price and directing them to public schools, public programs and social organisations. PNAE and PAA have been identified by the GEF-funded Biodiversity for Food and Nutrition Project (BFN) as entry-points for potentially improving nutrition and livelihoods with links to native biodiversity. At least 30% of the food purchased with federal funds through PNAE must be bought directly from family farmers. Both initiatives include ethical standards and incentives of up to 30% in the price for organic or agroecological produce, prioritising purchases from quilombolas and indigenous communities, while also supporting family agriculture organisations to rescue, produce, store, and distribute seeds of local or traditional varieties. This creates new opportunities for the use of resources from Brazilian ecosystems, promoting institutional markets for biodiversity products while providing incentives for the management and sustainable use of agricultural biodiversity. However, assessments reveal that the proportion of food products from native biodiversity purchased overall by PNAE and PAA are low, which also reflects the current status of Brazilian agriculture, based mostly on exotic species. In order to better mainstream biodiversity into PNAE and PAA, the BFN Project in Brazil is working to increase awareness on the importance and nutritional value of native biodiversity species. Advocacy workshops, capacity building, as well as strategic alliances and partnerships with policy makers and other stakeholders are an important element of this, as are contributions to policy instruments that impact both programs. BFN also engages with Federal Universities, which are also collaborating centres for the implementation of PNAE, in research partnerships and activities to conduct analysis on the nutritional composition of 70 prioritised native fruit species and work with traditional communities to assess the knowledge and use of biodiversity foods

Analyses of DNA damage in Saccharomyces cerevisiae mutant strains affected in the cell integrity (PKC) signaling pathway

The PKC signaling pathway is known to be related to genome integrity. Inclusively, it has already been shown that this pathway transmits information to the nucleus in what concerns genotoxic stress. Although this has been demonstrated it has not been shown that in the absence of a functional PKC pathway cells accumulate DNA damage. This research intends to investigate DNA damage caused by genotoxic stresses, as the one caused by the DNA replication inhibitor drug hydroxyurea, UV radiation and a genotoxic propolis extract, on mutants affected in the PKC pathway. The objective is to test the sensitivity of mutants affected in the genes BCK1, MKK1, MKK2 and SLT2, all fundamental MAPKs of this pathway. The biological model chosen for these experiments is Saccharomyces cerevisiae. As expected the results show higher sensitivity of the mutant strains when exposed to the genotoxicants, when compared to the parental strain, suggesting that PKC-defective mutants have decreased ability to repair DNA damage.info:eu-repo/semantics/publishedVersio

Drug-drug interactions and adverse drug reactions in polypharmacy among older adults: an integrative review

OBJECTIVE: To identify and summarize studies examining both drug-drug interactions (DDI) and adverse drug reactions (ADR) in older adults polymedicated. METHODS: An integrative review of studies published from January 2008 to December 2013, according to inclusion and exclusion criteria, in MEDLINE and EMBASE electronic databases were performed. RESULTS: Forty-seven full-text studies including 14,624,492 older adults (≥ 60 years) were analyzed: 24 (51.1%) concerning ADR, 14 (29.8%) DDI, and 9 studies (19.1%) investigating both DDI and ADR. We found a variety of methodological designs. The reviewed studies reinforced that polypharmacy is a multifactorial process, and predictors and inappropriate prescribing are associated with negative health outcomes, as increasing the frequency and types of ADRs and DDIs involving different drug classes, moreover, some studies show the most successful interventions to optimize prescribing. CONCLUSIONS: DDI and ADR among older adults continue to be a significant issue in the worldwide. The findings from the studies included in this integrative review, added to the previous reviews, can contribute to the improvement of advanced practices in geriatric nursing, to promote the safety of older patients in polypharmacy. However, more research is needed to elucidate gaps

Caracterização morfológica de híbridos interespecíficos de maracujazeiro (Passiflora spp.).

O presente trabalho teve como objetivo utilizar descritores morfológicos de 17 híbridos interespecíficos provenientes do cruzamento entre Passiflora edulis Sims e Passiflora cincinnatta Mast. Os parentais P. edulis (BGM330) e P. cincinnatta (BGM077), bem como os 21 híbridos resultantes deste cruzamento foram caracterizados com uso de 27 descritores qualitativos incluindo atributos relacionados à folha e flor, no período de abril a julho de 2011. As flores foram coletadas obedecendo-se o horário de abertura para cada acesso e, as medições foram obtidas com o auxílio de paquímetro.PDF. 083_11

A study on the convergence of observer-based kinetics estimators in stirred tank bioreactors

This paper is devoted to the tuning problem of the "observer-based kinetics estimator" in stirred tank bioreactors. This algorithm estimates the reaction kinetics from the on-line knowledge of the state variables (either from measurement or by means of state observer), when the yield coefficients are known. The relation between the dynamics of convergence and the tuning procedure is explored. The method proposed imposes a second-order dynamics to the convergence of the estimator. This approach will be shown to compare favourably with a pole placement based technique, in an application to a baker's yeast fed-batch fermentation.Junta Nacional de Investigação Científica e Tecnológica (JNICT) - contract numbers BIC/636/92, BD/224/90-IF, BD/1476/91-RM

CdTe detector based PIXE mapping of geological samples

A sample collected from a borehole drilled approximately 10 km ESE of Bragança, Trás-os-Montes, was analysed by standard and high energy PIXE at both CTN (previous ITN) PIXE setups. The sample is a fine-grained metapyroxenite grading to coarse-grained in the base with disseminated sulphides and fine veinlets of pyrrhotite and pyrite. Matrix composition was obtained at the standard PIXE setup using a 1.25 MeV H+ beam at three different spots. Medium and high Z elemental concentrations were then determined using the DT2fit and DT2simul codes (Reis et al., 2008, 2013 [1] and [2]), on the spectra obtained in the High Resolution and High Energy (HRHE)-PIXE setup (Chaves et al., 2013 [3]) by irradiation of the sample with a 3.8 MeV proton beam provided by the CTN 3 MV Tandetron accelerator. In this paper we present results, discuss detection limits of the method and the added value of the use of the CdTe detector in this context