7,987 research outputs found

    Symbolic approach to 2-orthogonal polynomial solutions of a third order differential equation

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    In a recent work, a generic differential operator on the vectorial space of polynomial functions was presented and applied in the study of differential relations fulfilled by polynomial sequences either orthogonal or 2-orthogonal. Considering a third order differential operator that does not increase the degree of polynomials, we search for polynomial eigenfunctions with the help of symbolic computations, assuming that those polynomials constitute a 2-orthogonal polynomial sequence. Two examples are extensively described.4516-0A1C-E9CD | Teresa Augusta MesquitaN/

    Importância e métodos de controle do "moleque" ou broca-do-rizoma-da-bananeira.

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    É no rizoma que se encontra a principal praga da bananicultura brasileira. Trate-e da especie Cosmopolites sordidus Gemar 1824, conhecida vulgarmente como "moleque", broca-do-rizoma ou broca-da-bananeira; Decricao e ciclo biológico; Danos e importância econômica; Medidas de controle; Utilizacao de mudas livres de infestacao; Utilizacao de iscas atrativas; Variedades resistentes; Controle biologico; Controle quimico; Controle por comportamentobitstream/CNPAT-2010/8608/1/Ci-017.pd

    Handball coaches' perceptions about the value of working competences according to their coaching background

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    The purpose of this study was to analyze the value attributed to given working competences, by Portuguese handball coaches according to their coaching background, certification level, coaching experience, and level of education. A sample of 207 handball coaches responded to a questionnaire which included demographic characteristics and a scale focused on perceptions of the level of importance attributed to working competences. Data analysis included an exploratory factorial analysis applying Maximum Likelihood Factoring (MLF) and Oblimin rotation. These factors were submitted to a One-way ANOVA and Tukey's post hoc multiple comparisons to analyse coaches' perceptions according to their coaching background. A six factor solution was found where three major domains of competences were highlighted; the first one related to training and competition (e.g. planning and conducting the training, team administration in competition, annual and multi-annual planning, and coaching methodology); the second one related to social and cultural issues and management (e.g. implementation of youth sport development projects, team leadership and coach education) and the third one related to the cognitive background (meta-cognitive competences). The importance ascribed to some working competences was influenced by their coaching experience and certification level. Highly experienced and qualified coaches perceived competences of everyday practice, social, cultural and management issues related to training and competition as more important than the other coaches. This study suggests the need to consider some working competences, until now not explicitly present in the Portuguese coaching education curriculum which could enable coaches to choose the best way to practice/work in a manner that will foster and support their professional development. Key pointsThree major domains of competences were highlighted by Portuguese handball coaches. The first one related to training and competition, the second one related to social and cultural issues and management and the third one related to the cognitive background.The importance ascribed by Portuguese handball coaches to some working competences was influenced by their coaching experience and certification level, as high experienced coaches and coaches with higher certification levels perceived competences related to training and competition of the everyday practice and social, cultural issues and management as more important.The value attributed by Portuguese handball coaches to working competences did not vary according to the coaches' academic education level.Portuguese handball coaches valued the meta-cognitive competences, the competences to implement sport development project and related to annual and multi-annual planning independently of their coaching background

    Acumulação de polihidroxialcanoatos por culturas microbianas mistas do tratamento do efluente urbano

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    Os microrganismos podem acumular intracelularmente inclusões de polihidroxialcanoatos (PHAs) durante o tratamento de águas residuais, utilizando o efluente urbano como fonte de carbono. Estes polímeros biodegradáveis surgem como alternativa aos plásticos convencionais, permitindo reduzir a quantidade de lamas enviadas para tratamento posterior. A monitorização da acumulação de PHAs nos microrganismos das lamas ativadas da ETAR de Penices foi efetuada durante 30 dias, recorrendo ao método de Cromatografia Gasosa (CG) e à técnica de coloração de Negro Sudão B (NSB). Os resultados obtidos por CG revelaram uma acumulação máxima, em fração mássica, de PHAs igual a 5.3 % nas lamas ativadas, relativamente ao teor de biomassa liofilizada e uma concentração máxima de 127 mg L-1. Os resultados obtidos por NSB corroboraram estes valores, pelo que esta técnica poderá ser uma alternativa viável para a quantificação de PHAs, sendo mais fácil de operar e menos dispendiosa. Concluiu-se ainda que a produção de PHAs com culturas mistas à escala industrial para este caso de estudo não é viável, dadas as baixas quantidades obtidas de polímero e o elevado investimento em unidades de extração e purificação do mesmo.The microorganisms can accumulate intracellularly inclusions of polyhydroxyalkanoates (PHAs) during wastewater treatment, using the urban efluent as carbon source. These biodegradable polymers appear to emerge as an alternative to conventional plastics, allowing to reduce the amount of activated sludge sent to posterior treatment. The monitoring of the PHAs accumulation in the activated sludge microorganisms of the Penices wastewater treatment facility was performed for 30 days, using gas chromatography (GC) and Sudan Black B (SBB) staining. GC results revealed a maximum accumulation of PHAs mass fraction of 5.3 % in the activated sludge, in relation to the liophilized biomass content, and a maximum concentration of 127 mg L -1 . The SBB results corroborated these values, and therefor this technique can be a viable alternative to the PHAs quantification, being easier to operate and less costly. Still, it was possible to conclude that the PHAs production with mixed cultures at the industrial scale is not viable in this case, given the obtained low quantities of polymer and the high investment in extraction and purification units

    On the Practical Use in Hydrography of Filtered Daily Values of Mean Sea Level

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    It is shown that the mean monthly sea level of a non-permanent station can be referred to the long-term sea level of a permanent one when tidal stations are influenced by similar meteorological and oceanographical effects. Practical methods are derived : one is based on the direct transference and the other based on the ratio of the variances of the daily mean sea level. Applications of the methods are made for the ports of Cananeia, Ubatuba, Santos and Ilha Grande on the southern coast of Brazil

    Shotguns vs Lasers: Identifying barriers and facilitators to scaling-up plant molecular farming for high-value health products.

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    Plant molecular farming (PMF) is a convenient and cost-effective way to produce high-value recombinant proteins that can be used in the production of a range of health products, from pharmaceutical therapeutics to cosmetic products. New plant breeding techniques (NPBTs) provide a means to enhance PMF systems more quickly and with greater precision than ever before. However, the feasibility, regulatory standing and social acceptability of both PMF and NPBTs are in question. This paper explores the perceptions of key stakeholders on two European Union (EU) Horizon 2020 programmes-Pharma-Factory and Newcotiana-towards the barriers and facilitators of PMF and NPBTs in Europe. One-on-one qualitative interviews were undertaken with N = 20 individuals involved in one or both of the two projects at 16 institutions in seven countries (Belgium, France, Germany, Italy, Israel, Spain and the UK). The findings indicate that the current EU regulatory environment and the perception of the public towards biotechnology are seen as the main barriers to scaling-up PMF and NPBTs. Competition from existing systems and the lack of plant-specific regulations likewise present challenges for PMF developing beyond its current niche. However, respondents felt that the communication of the benefits and purpose of NPBT PMF could provide a platform for improving the social acceptance of genetic modification. The importance of the media in this process was highlighted. This article also uses the multi-level perspective to explore the ways in which NPBTs are being legitimated by interested parties and the systemic factors that have shaped and are continuing to shape the development of PMF in Europe
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