8,958 research outputs found

    Heterotrophy as a tool to overcome the long and costly autotrophic scale-up process for large scale production of microalgae

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    Industrial scale-up of microalgal cultures is often a protracted step prone to culture collapse and the occurrence of unwanted contaminants. To solve this problem, a two-stage scale-up process was developed - heterotrophically Chlorella vulgaris cells grown in fermenters (1st stage) were used to directly inoculate an outdoor industrial autotrophic microalgal production unit (2nd stage). A preliminary pilot-scale trial revealed that C. vulgaris cells grown heterotrophically adapted readily to outdoor autotrophic growth conditions (1-m3 photobioreactors) without any measurable difference as compared to conventional autotrophic inocula. Biomass concentration of 174.5 g L-1, the highest value ever reported for this microalga, was achieved in a 5-L fermenter during scale-up using the heterotrophic route. Inocula grown in 0.2- and 5-m3 industrial fermenters with mean productivity of 27.54 ± 5.07 and 31.86 ± 2.87 g L-1 d-1, respectively, were later used to seed several outdoor 100-m3 tubular photobioreactors. Overall, all photobioreactor cultures seeded from the heterotrophic route reached standard protein and chlorophyll contents of 52.18 ± 1.30% of DW and 23.98 ± 1.57 mg g-1 DW, respectively. In addition to providing reproducible, high-quality inocula, this two-stage approach led to a 5-fold and 12-fold decrease in scale-up time and occupancy area used for industrial scale-up, respectively.Agência financiadora project FERMALG 017608 Fundacao para a Ciencia e a Tecnologia (FCT) UID/Multi/04326/2019 project FERMALG (AVISO) 32/SI/2015info:eu-repo/semantics/publishedVersio

    Seismic strengthening of beam-column joints with multidirectional CFRP laminates

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    An experimental program was carried out to analyse the potentialities of a technique based on the use of multidirectional CFRP laminates (MDL-CFRP) for the seismic repair and strengthening of reinforced concrete (RC) beam-column joints. This experimental program comprises cyclic tests on three full-scale RC joints, representative of interior beam-column connections in buildings. The joints were initially submitted to a cyclic test inducing a damage pattern representative of a seismic event. Subsequently, they were repaired and strengthened with MDL-CFRP. The strengthened joints were then tested for the same loading history of the original ones up to their failure. The adopted strengthening technique uses the MDL-CFRP that are simultaneously glued and anchored to the concrete surfaces. This technique is called Mechanically Fastened and Externally Bonded Reinforcement (MF-EBR). In the present study, the effectiveness of two different strengthening configurations was investigated. The tests are described and the main results are presented and analyzed

    Entropy, diffusivity and the energy landscape of a water-like fluid

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    Molecular dynamics simulations and instantaneous normal mode (INM) analysis of a fluid with core-softened pair interactions and water-like liquid-state anomalies are performed to obtain an understanding of the relationship between thermodynamics, transport properties and the poten- tial energy landscape. Rosenfeld-scaling of diffusivities with the thermodynamic excess and pair correlation entropy is demonstrated for this model. The INM spectra are shown to carry infor- mation about the dynamical consequences of the interplay between length scales characteristic of anomalous fluids, such as bimodality of the real and imaginary branches of the frequency distribu- tion. The INM spectral information is used to partition the liquid entropy into two contributions associated with the real and imaginary frequency modes; only the entropy contribution from the imaginary branch captures the non-monotonic behaviour of the excess entropy and diffusivity in the anomalous regime of the fluid

    Reforço sísmico de estruturas de alvenaria com recurso a elementos metálicos

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    Neste estudo ilustram-se alguns dos diversos tipos de reforço sísmico de estruturas de alvenaria com recurso a elementos metálicos. A abordagem pormenorizada de cada elemento de reforço permite compreender o funcionamento individual dos mesmos, possibilitando a determinação de soluções adequadas a cada caso. A solução abordada no caso de estudo enquadra-se dentro do panorama nacional e internacional da reabilitação sísmica, tendo sido adoptada em intervenções efectuadas sobre edificações nos Açores, visando a prevenção de danos nas edificações decorrentes de novos fenómenos sísmicos. Tecnicamente, esta abordagem permite, com rigor, simplicidade e eficácia, reduzir a vulnerabilidade sísmica das estruturas de alvenaria de pedra face à acção sísmica, resolvendo globalmente o problema da estabilidade e da resistência, com base no recurso a elementos metálicos

    Impact of macro-socioeconomic determinants on perinatal healthcare quality for very preterm infants

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    The WHO identified the importance of macro-socioeconomic determinants and the political context as interlinked key factors affecting health equity. The 2008 economic crisis was associated with a significant low-birth-weight increase in Portugal, 2007-2014. The Economic Adjustment Programme (EAP), implemented to economize non-essential health care costs (2011-2014), substantially affected healthcare delivery and occupational environment of Healthcare Professionals (HCPs). This study aims to analyse the impact observed by HCPs of the economic crisis and EAP on equitable quality of perinatal healthcare for very preterm infants in Portugal. A Qualitative study design with 21 HCPs in clinical settings equally distributed among Portuguese mainland were selected according to their response. Semi-structured interviews were conducted between October 2018-April 2019 until saturation point was achieved. A content analysis was performed using Nvivo2011 software. Preliminary results on macro-socioeconomic determinants, classified and conceptualized into a three-stage-effect framework, disclosed an interrelation between factors impacting perinatal healthcare quality, according to HCPs. Primary-stage: increase in working hours and patient-ratio per HCPs, cuts in salaries and investment, increasing waiting time and HCPs demotivation. Secondary-stage: burnout, work-absence, time constraints, decreasing quality and consultation availability. Tertiary-stage: HCPs Brain-drain to private sector, double-shifts in public-private sector, increasing inadequacy of transmissivity within sector communication. The economic crisis and EAP were perceived to have modified equitable perinatal healthcare quality for very preterm infants in Portugal. Increased private-public sector transparency to maximise quality assurance, equal HCP wage distribution to sustain capability, strengthening of social maternity protection strategies to enhance socioeconomic equity in perinatal healthcare, is recommended

    Focus and coverage of Bolsa Família Program in the Pelotas 2004 birth cohort

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    OBJECTIVE To describe the focalization and coverage of Bolsa Família Program among the families of children who are part of the 2004 Pelotas birth cohort (2004 cohort). METHODS The data used derives from the integration of information from the 2004 cohort and the Cadastro Único para Programas Sociais do Governo Federal (CadÚnico – Register for Social Programs of the Federal Government), in the 2004-2010 period. We estimated the program coverage (percentage of eligible people who receive the benefit) and its focus (proportion of eligible people among the beneficiaries). We used two criteria to define eligibility: the per capita household income reported in the cohort follow-ups and belonging to the 20% poorest families according to the National Economic Indicator (IEN), an asset index. RESULTS Between 2004 and 2010, the proportion of families in the cohort that received the benefit increased from 11% to 34%. We observed an increase in all wealth quintiles. In 2010, by income and wealth quintiles (IEN), 62%-72% of the families were beneficiaries among the 20% poorest people, 2%-5% among the 20% richest people, and about 30% of families of the intermediate quintile. According to household income (minus the benefit) 29% of families were eligible in 2004 and 16% in 2010. By the same criteria, the coverage of the program increased from 43% in 2004 to 71% in 2010. In the same period, by the wealth criterion (IEN), coverage increased from 29% to 63%. The focalization of the program decreased from 78% in 2004 to 32% in 2010 according to income, and remained constant (37%) according to the IEN. CONCLUSIONS Among the families of the 2004 cohort, there was a significant increase in the program coverage, from its inception until 2010, when it was near 70%. The focus of the program was below 40% in 2010, indicating that more than half of the beneficiaries did not belong to the target population.OBJETIVO Descrever a focalização e a cobertura do Programa Bolsa Família nas famílias de crianças que fazem parte da coorte de nascimentos de Pelotas, 2004 (coorte de 2004). MÉTODOS Os dados utilizados derivam da integração de informações da coorte de 2004 e do Cadastro Único para Programas Sociais do Governo Federal, no período de 2004 a 2010. Estimamos a cobertura do programa (percentual de elegíveis que recebem bolsa) e seu foco (proporção de elegíveis entre os beneficiários). Utilizamos dois critérios para definir elegibilidade: a renda familiar per capita relatada nas avaliações da coorte e pertencer aos 20,0% mais pobres pela classificação do Indicador Econômico Nacional, um índice de bens. RESULTADOS Entre 2004 e 2010, a proporção de famílias beneficiárias da coorte passou de 11% para 34%. Houve aumento em todos os quintis de riqueza. Em 2010, por quintis de renda e Indicador Econômico Nacional, 62%-72% das famílias eram beneficiárias entre os 20% mais pobres, 2%-5% entre os 20% mais ricos, e cerca de 30% das famílias do quintil intermediário. Pelo critério de renda familiar, excluindo-se o valor do benefício do programa, 29% das famílias eram elegíveis em 2004 e 16% em 2010. Pelo mesmo critério, a cobertura do programa passou de 43% em 2004 para 71% em 2010. No mesmo período, pelo critério de riqueza (Indicador Econômico Nacional), a cobertura passou de 29% para 63%. A focalização do programa caiu de 78% em 2004 para 32% em 2010 de acordo com a renda e permaneceu constante (37%) de acordo com o Indicador Econômico Nacional. CONCLUSÕES Entre as famílias da coorte de 2004, observa-se aumento importante da cobertura do programa, de seu início até 2010, quando ficou perto de 70%. O foco do programa ficou abaixo de 40% em 2010, indicando que mais da metade dos beneficiários não pertencem à população alvo

    Prevalence and duration of breast milk feeding in very preterm infants: A 3-year follow-up study and a systematic literature review

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    Background: The World Health Organization recommends exclusive breast milk feeding until 6 months and continuing up to 2 years of age; little is known about whether very preterm infants are fed in accordance with these recommendations. We aimed to describe the prevalence and duration of breast milk feeding in very preterm children and to systematically review internationally published data. Methods: We evaluated breast milk feeding initiation and duration in very preterm children born in 2 Portuguese regions (2011‐2012) enrolled in the EPICE cohort and followed‐up to the age of 3 (n = 466). We searched PubMed® from inception to January 2017 to identify original studies reporting the prevalence and/or duration of breast milk feeding in very preterm children. Results: 91.0% of children received some breast milk feeding and 65.3% were exclusively breast fed with a median duration of 2 months for exclusive and 3 months for any breast milk; only 9.9% received exclusive breast milk for at least 6 months, 10.2% received any breast milk for 12 months or more, and 2.0% for up to 24 months. The literature review identified few studies on feeding after hospital discharge (n = 9); these also reported a low prevalence of exclusive breast milk feeding at 6 months (1.0% to 27.0%) and of any breast milk at 12 months (8.0% to 12.0%). Conclusions: The duration of breast milk feeding among Portuguese very preterm infants was shorter than recommended. However, this appears to be common globally. Research is needed to inform strategies to promote continued breast milk feeding.This study was funded by the European Union Seventh Framework Programme (FP7/2007‐2013) under grant agreement no. 259882. This study was also funded by FEDER through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology—FCT (Portuguese Ministry of Science, Technology and Higher Education), under the Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (POCI‐01‐0145‐FEDER‐006862; Ref.UID/DTP/04750/2013); the PhD Grant SFRH/BD/111794/2015 (Carina Rodrigues) and the individual grant SFRH/BSAB/113778/2015 (Henrique Barros), co‐funded by the FCT and the POCH/FSE Program
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