3,885 research outputs found

    Management of Operational Parameters and Novel Spinneret Configurations for the Electrohydrodynamic Processing of Functional Polymers

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    [EN] Functional materials have become key drivers in the development of multiple high-end technologies. Electrohydrodynamic processing (EHDP) is a straightforward method to generate polymer micro- and nanostructures that can be applied to the food, pharmaceutical, environmental, and biomedical areas, among others, since these can yield materials with higher performance. Some of the EHDP's advantages over other polymer processing technologies rely on its high versatility, by which the final assembly can be modified in different ways to combine materials with multiple properties and also in different morphological structures, and the use of room processing conditions, meaning that thermolabile ingredients can be incorporated with minimal activity loss. This review provides the historical background, process basics, and the state-of-the-art of the most recent advances achieved in the EHDP technology dealing with the control of its operational parameters to optimize processability and achieve end-product quality and homogeneity. It also focuses on the newly developed modes of operation and spinneret configurations that can lead to the formation of a wide range of micro- and nanostructures with different functionalities and solve some of its current technical limitations. Finally, it also further highlights the potential applications of the resultant hierarchical functional polymer-based materials obtained by these novel EHDP methods.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and by the I&D&I AgriFood XXI project, operation number NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (FEDER) under the scope of NORTE 2020 (ProgramaOperacional Regional do Norte 2014/2020). Pedro Silva is the recipient of a fellowship (SFRD/BD/130247/2017) supported by FCT. S. TorresGiner acknowledges Spanish Ministry of Science and Innovation (MICI) for the funding received during his Ramon y Cajal contract (RYC2019027784-I).Silva, PM.; Torres-Giner, S.; Vicente, AA.; Cerqueira, MA. (2022). Management of Operational Parameters and Novel Spinneret Configurations for the Electrohydrodynamic Processing of Functional Polymers. Macromolecular Materials and Engineering. 307(5):1-21. https://doi.org/10.1002/mame.202100858121307

    Sunki mandarin and Swingle citrumelo as rootstocks for rain-fed cultivation of late-season sweet orange selections in northern São Paulo state, Brazil.

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    In Brazilian regions affected by the citrus sudden death disease, sweet orange cultivation depends on the use of resistant rootstocks. Rangpur lime was mainly replaced by Swingle citrumelo and Sunki mandarin rootstocks, more drought-sensitive ones. The diversification of scion selections is also desirable aiming at the increasing demand for not from concentrate orange juice (NFC) that requires high-quality fruits. In this work, we evaluated the performance of 6 selections of Valencia (IAC, Dom João, Late Burjasot IVIA 35-2, Rhode Red SRA 360, Temprana IVIA 25 and Campbell) and Natal IAC sweet oranges grafted onto Swingle citrumelo and Sunki mandarin. The planting occurred in 2001 under rain-fed cultivation in Bebedouro, northern São Paulo state, Brazil. The outline was made through randomized blocks in a 7 × 2 factorial design (selections × rootstock), with 4 replications and 2 trees in unit. Both rootstocks performed well in the region. Sunki mandarin rootstock induced greater tree size and production per plant to the scion selections, 38 and 21%, respectively, plus higher precocity of production compared to Swingle citrumelo. The later determined a greater productive efficiency, as well as a greater percentage of juice in general, albeit with lower concentrations of soluble solids and acidity. Natal IAC, Valencia IAC and Rhode Red Valencia selections presented a higher accumulated production, on average, 218.6 kg?plant?1 (2004 ? 2008), and a higher productive efficiency (kg fruit?m?3 of canopy) due to their smaller tree size. All assessed selections produced fruits with high soluble solids content that were suitable for juice processing

    Caracterização de híbridos ornamentais de bananeira.

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    As fruteiras ornamentais são uma alternativa para o segmento da floricultura, possuem grande plasticidade de uso podendo ser apreciadas como plantas de parques, jardins, flores de corte, plantas de vaso, folhagens e minifrutos ornamentais. O Banco de Germoplasma de Bananeira da Embrapa Mandioca e Fruticultura possui acessos de diferentes seções do gênero Musa.PDF. 120_11

    Avaliação química e biológica da proteína do grão em cultivares de milho de alta qualidade protéica.

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    Cultivares de milho de alta qualidade protéica (QPM) desenvolvidos pela Embrapa Milho e Sorgo foram avaliados quanto ao conteúdo de aminoácidos essenciais e aproveitamento biológico da proteína, em ratos Wistar machos, recém-desmamados. Sete grupos de seis animais foram mantidos durante dez dias sob condições ambientais padronizadas, recebendo cada grupo uma das seguintes rações: a) controle a 10% e a 7% de proteína (caseína), b) aprotéica, c) experimentais com milho a 7% de proteína (QPM amarelo - BR 473, QPM branco - BR 451 e milho comum - BR 136), d) mistura arroz-feijão a 10% de proteína (1:1 em base protéica). A qualidade protéica do milho BR 473 foi semelhante à do milho BR 451 e significativamente superior (p<O,05) à do milho BR 136, segundo os índices NPR (Net Protein Ratio- 3,37; 3,54 e 2,58, respectivamente para BR 473, BR 451 e BR 136) e NPU (Net Protein Utilization - 56%,58% e 43%, respectivamente). Os milhos QPM possuem valor protéico elevado (média de 83% em relação à proteína de referência), similar ao da mistura arroz-feijão, constituindo-se em alimentos promissores para uso em programas de combate à desnutrição no Brasil, em especial para crianças de baixa renda

    Seleção de híbridos de bananeira com potencial para minifrutos ornamentais e paisagismo.

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    O mercado de plantas ornamentais está sempre em busca de novos produtos. A bananeira é uma fruteira tropical de porte médio a alto, com folhagem verde exuberante e frutos geralmente de coloração verde a amarela. A geração de plantas de pequeno porte com coloração de frutos e inflorescência masculina variados, que possam ser cultivadas em espaços reduzidos, assim como a opção de se utilizar frutos pequenos em arranjos ornamentais é um diferencial interessante para o mercado de floricultura tropical.PDF.69

    Cognitive appraisal in fish: stressor predictability modulates the physiological and neurobehavioural stress response in sea bass

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    The role of cognitive factors in triggering the stress response is well established in humans and mammals (aka cognitive appraisal theory) but very seldom studied in other vertebrate taxa. Predictability is a key factor of the cognitive evaluation of stimuli. In this study, we tested the effects of stressor predictability on behavioral, physiological and neuromolecular responses in the European sea bass (Dicentrarchus labrax). Groups of four fish were exposed to a predictable (signalled) or unpredictable (unsignalled) stressor. Stressor predictability elicited a lower behavioural response and reduced cortisol levels. Using the expression of immediate early genes (c-fos, egr-1, bdnf and npas4) as markers of neuronal activity, we monitored the activity of three sea bass brain regions known to be implicated in stressor appraisal: the dorsomedian telencephalon, Dm (putative homologue of the pallial amygdala); and the dorsal (Dld) and ventral (Dlv) subareas of the dorsolateral telencephalon (putative homologue of the hippocampus). The activity of both the Dm and Dlv significantly responded to stressor predictability, suggesting an evolutionarily conserved role of these two brain regions in information processing related to stressor appraisal. These results indicate that stressor predictability plays a key role in the activation of the stress response in a teleost fish, hence highlighting the role of cognitive processes in fish stress.info:eu-repo/semantics/publishedVersio

    Relación entre la condición corporal y medidas de grasa y de músculo obtenidas por ultrasonografía en tiempo real con vacas de raza Barrosã

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    publishedTomo I . Sección: Sistemas Ganaderos-Economía y Gestión. Sesión: Vacuno carne II. Ponencia nº 1

    Alterações de açúcares e amido em Banana 'Grande Naine' durante o amadurecimento.

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    A banana do cultivar 'Grande Naine' pertence ao grupo AAA, subgrupo Cavendish, com grande capacidade produtiva. Durante o desenvolvimento a banana acumula amido, podendo atingir acima de 20% do peso fresco do fruto. Após o pico de etileno e concomitante pico respiratório esta reserva é rapidamente mobilizada, podendo cair para níveis abaixo de 1% ao mesmo tempo em que ocorre a elevação na concentração de sólidos solúveis para valores próximos a 12%. Esse trabalho teve como objetivo avaliar as transformações relativas aos teores de amido e açúcares ao longo do amadurecimento de banana do cultivar 'Grande Naine', gerando informações sobre esta cultivar para o programa de melhoramento genético. Foram realizadas análises de teor de amido, teor de sólidos solúveis, açúcares totais e redutores. O delineamento experimental foi IC com 6 repetições de 2 frutos. O avanço pelos estádios de amadurecimento refletiu na redução dos teores de amido e aumento dos sólidos solúveis. As principais mudanças nas variáveis estudadas foram observadas entre os estádios 3 e 4. Com os dados obtidos foi possível acompanhar o comportamento do metabolismo dos açúcares da banana 'Grande Naine' produzida em Cruz das Almas

    Hybrid Method Based on NARX models and Machine Learning for Pattern Recognition

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    This work presents a novel technique that integrates the methodologies of machine learning and system identification to solve multiclass problems. Such an approach allows to extract and select sets of representative features with reduced dimensionality, as well as predicts categorical outputs. The efficiency of the method was tested by running case studies investigated in machine learning, obtaining better absolute results when compared with classical classification algorithms.Comment: In English. SBAI 2021 - Brazilian Symposium on Intelligent Automation (SBAI - Simposio Brasileiro de Automacao Inteligente). 6 pages. 4 figure

    A Survey on Long-Range Wide-Area Network Technology Optimizations

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    Long-Range Wide-Area Network (LoRaWAN) enables flexible long-range service communications with low power consumption which is suitable for many IoT applications. The densification of LoRaWAN, which is needed to meet a wide range of IoT networking requirements, poses further challenges. For instance, the deployment of gateways and IoT devices are widely deployed in urban areas, which leads to interference caused by concurrent transmissions on the same channel. In this context, it is crucial to understand aspects such as the coexistence of IoT devices and applications, resource allocation, Media Access Control (MAC) layer, network planning, and mobility support, that directly affect LoRaWAN’s performance.We present a systematic review of state-of-the-art works for LoRaWAN optimization solutions for IoT networking operations. We focus on five aspects that directly affect the performance of LoRaWAN. These specific aspects are directly associated with the challenges of densification of LoRaWAN. Based on the literature analysis, we present a taxonomy covering five aspects related to LoRaWAN optimizations for efficient IoT networks. Finally, we identify key research challenges and open issues in LoRaWAN optimizations for IoT networking operations that must be further studied in the future
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