2,239 research outputs found

    Flow behaviour in microchannels of an innovative blood analogue fluid based on giant unilamellar vesicles

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    This work focused on the development of an innovative blood analogue, containing giant unilamellar vesicles (GUVs), to mimic the flow behaviour of red blood cells (RBCs). The rheological characterization of different blood analogue solutions was performed in a stress controlled rheometer and the results have shown a good agreement when compared with a sample containing 5% of RBCs.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. The authors also acknowledge the financial support provided by FCT through the project PTDC/QEQ-FTT/4287/2014.info:eu-repo/semantics/publishedVersio

    A amplitude amostral interfere nas medidas de germinação de Bowdichia virgilioides Kunth?

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    http://dx.doi.org/10.5902/1980509812346It is usual to find papers about seed germination of native species using different sample sizes. However, theconsequences of these procedures on the results are unknown. This study measured the germination processof Bowdichia virgilioides based on different seed sample sizes. The assay was conducted in a germinationchamber under continuous fluorescent white lamps and 26.2 ± 2.5 ºC. The design was completelyrandomized, as a 3 x 3 factorial (three sample sizes x three seed lots), with four replications per treatment.The sowing was done in gerbox, each one containing 25 seeds, making up 100, 200 and 400 seeds persample analyzed. Germinability, time (first, average and final), speed (mean germination rate and Maguire’sindex – VE or IVG), coefficient of variation of the germination time, uncertainty and synchrony of thegermination process were evaluated. Those seeds with embryo protrusion were considered germinated.Germination relative frequency graphics were also made. Among these measurements, the most fragile to size sample were VE and the uncertainty. VE was also influenced by the relation between germinability andmean germination rate, demonstrating its instability to measure the speed of the germination process whenthe lots have different germination capacity. Results of time measurements, uniformity, mean germinationrate and germinability were not affected by seed sample size. Germinability, however, was the most stablegermination measurement, and was not affected by sample size, even when analyzed by seed lots with verydiscrepant quality.http://dx.doi.org/10.5902/1980509812346É comum encontrar na literatura trabalhos sobre germinação de sementes nativas de uma mesma espécie com tamanhos de amostra diferenciados. No entanto, não se sabe quais são as consequências disso para os resultados obtidos. Assim, objetivou-se estudar o comportamento das medidas de germinação frente à variação do número de sementes que compõe a amostra para Bowdichia virgilioides. O experimento foi conduzido em câmara de germinação, sob luz branca fluorescente contínua, a 26,2 ± 2,5 ºC. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial 3 x 3 (três tamanhos de amostra x três lotes), com número de repetições fixo e igual a quatro. A semeadura foi realizada em caixas tipo gerbox, contendo 25, 50 ou 100 sementes, perfazendo 100, 200 ou 400 sementes por amostra. A germinabilidade, tempo inicial, médio e final, velocidade média e VE (IVG), coeficiente de variação do tempo, incerteza e sincronia da germinação foram avaliados, sendo consideradas germinadas as sementes com protrusão de embrião. Gráficos de frequência relativa também foram construídos. Dentre estas medidas, as mais frágeis ao incremento do tamanho da amostra foram o VE e a incerteza. O VE, além de ser influenciado pelo tamanho da amostra, também foi influenciado pelo contrabalancear entre germinabilidade e velocidade média, demonstrando ser uma medida imprópria para mensurar velocidade de germinação quando a capacidade germinativa dos lotes for diferente. As medidas de tempo, uniformidade, sincronia, velocidade média e a germinabilidade não tiveram seus resultados afetados pelos diferentes tamanhos da amostra. A germinabilidade, entretanto, mostrou-se a medida mais estável do processo germinativo, não sendo influenciada pelo tamanho da amostra, mesmo quando analisada por meio de lotes com qualidades muito discrepantes

    Meningoradiculitis Due To Cryptococcus Neofermans In An Immunocompetent Patient.

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    Meningoradiculitis refers to combined involvement of meninges and nerve roots. The most frequent location is the lumbosacral region. Etiology is diverse, including inflammatory, infectious and neoplastic disorders. Meningoradiculitis is a rare form of involvement in cryptococcal infection. We describe a case of subacute lower limbs flaccid paresis diagnosed as lumbosacral meningoradiculitis in view of cerebrospinal fluid (CSF) inflammatory changes and typical enhancement on MRI of lumbar spine. Cryptococcus neoformans was isolated from CSF. Extensive screening yielded no immunodeficiencies.62147-

    Microfluidic deformability study of an innovative blood analogue fluid based on giant unilamellar vesicles

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    Blood analogues have long been a topic of interest in biofluid mechanics due to the safety and ethical issues involved in the collection and handling of blood samples. Although the current blood analogue fluids can adequately mimic the rheological properties of blood from a macroscopic point of view, at the microscopic level blood analogues need further development and improvement. In this work, an innovative blood analogue containing giant unilamellar vesicles (GUVs) was developed to mimic the flow behavior of red blood cells (RBCs). A natural lipid mixture, soybean lecithin, was used for the GUVs preparation, and three different lipid concentrations were tested (1 × 10−3 M, 2 × 10−3 M and 4 × 10−3 M). GUV solutions were prepared by thin film hydration with a buffer, followed by extrusion. It was found that GUVs present diameters between 5 and 7 µm which are close to the size of human RBCs. Experimental flow studies of three different GUV solutions were performed in a hyperbolic-shaped microchannel in order to measure the GUVs deformability when subjected to a homogeneous extensional flow. The result of the deformation index (DI) of the GUVs was about 0.5, which is in good agreement with the human RBC’s DI. Hence, the GUVs developed in this study are a promising way to mimic the mechanical properties of the RBCs and to further develop particulate blood analogues with flow properties closer to those of real blood.COMPETE2020, NORTE2020, PORTUGAL2020, FEDER; FCT Project PTDC/QEQ-FTT/4287/2014 (POCI-01-0145-FEDER-016861); FCT Project PTDC/EMD-EMD/29394/2017 (NORTE-01-0145-FEDER-029394); FCT Project PTDC/EME-SIS/30171/2017 (NORTE-01-0145-FEDER-000032); FCT Project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020); SFRH/BD/99696/2014 PhD Grant;info:eu-repo/semantics/publishedVersio

    DOES THE SAMPLE RANGE INTERFERE IN THE GERMINATION MEASUREMENTS OF Bowdichia virgilioides Kunth?

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    \uc9 comum encontrar na literatura trabalhos sobre germina\ue7\ue3o de sementes nativas de uma mesma esp\ue9cie com tamanhos de amostra diferenciados. No entanto, n\ue3o se sabe quais s\ue3o as consequ\ueancias disso para os resultados obtidos. Assim, objetivou-se estudar o comportamento das medidas de germina\ue7\ue3o frente \ue0 varia\ue7\ue3o do n\ufamero de sementes que comp\uf5e a amostra para Bowdichia virgilioides . O experimento foi conduzido em c\ue2mara de germina\ue7\ue3o, sob luz branca fluorescente cont\uednua, a 26,2 \ub1 2,5 \ubaC. O delineamento utilizado foi o inteiramente casualizado, em esquema fatorial 3 x 3 (tr\ueas tamanhos de amostra x tr\ueas lotes), com n\ufamero de repeti\ue7\uf5es fixo e igual a quatro. A semeadura foi realizada em caixas tipo gerbox, contendo 25, 50 ou 100 sementes, perfazendo 100, 200 ou 400 sementes por amostra. A germinabilidade, tempo inicial, m\ue9dio e final, VElocidade m\ue9dia e VE (IVG), coeficiente de varia\ue7\ue3o do tempo, incerteza e sincronia da germina\ue7\ue3o foram avaliados, sendo consideradas germinadas as sementes com protrus\ue3o de embri\ue3o. Gr\ue1ficos de frequ\ueancia relativa tamb\ue9m foram constru\ueddos. Dentre estas medidas, as mais fr\ue1geis ao incremento do tamanho da amostra foram o VE e a incerteza. O VE , al\ue9m de ser influenciado pelo tamanho da amostra, tamb\ue9m foi influenciado pelo contrabalancear entre germinabilidade e VElocidade m\ue9dia, demonstrando ser uma medida impr\uf3pria para mensurar VElocidade de germina\ue7\ue3o quando a capacidade germinativa dos lotes for diferente. As medidas de tempo, uniformidade, sincronia, VElocidade m\ue9dia e a germinabilidade n\ue3o tiVEram seus resultados afetados pelos diferentes tamanhos da amostra. A germinabilidade, entretanto, mostrou-se a medida mais est\ue1VEl do processo germinativo, n\ue3o sendo influenciada pelo tamanho da amostra, mesmo quando analisada por meio de lotes com qualidades muito discrepantes.It is usual to find papers about seed germination of natiVE species using different sample sizes. HoweVEr, the consequences of these procedures on the results are unknown. This study measured the germination process of Bowdichia virgilioides based on different seed sample sizes. The assay was conducted in a germination chamber under continuous fluorescent white lamps and 26.2 \ub1 2.5 \ubaC. The design was completely randomized, as a 3 x 3 factorial (three sample sizes x three seed lots), with four replications per treatment. The sowing was done in gerbox, each one containing 25 seeds, making up 100, 200 and 400 seeds per sample analyzed. Germinability, time (first, aVErage and final), speed (mean germination rate and Maguire\u2019s index \u2013 VE or IVG), coefficient of variation of the germination time, uncertainty and synchrony of the germination process were evaluated. Those seeds with embryo protrusion were considered germinated. Germination relatiVE frequency graphics were also made. Among these measurements, the most fragile to size sample were VE and the uncertainty. VE was also influenced by the relation between germinability and mean germination rate, demonstrating its instability to measure the speed of the germination process when the lots haVE different germination capacity. Results of time measurements, uniformity, mean germination rate and germinability were not affected by seed sample size. Germinability, howeVEr, was the most stable germination measurement, and was not affected by sample size, eVEn when analyzed by seed lots with VEry discrepant quality

    Reference Model in BPMN Notation for a Production Scheduling System

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    Companies are progressively investing in practices aimed at improving the quality of management, with the main purpose of enabling them to operate competitively in the present market. For this, it is necessary to document the activities and information of the existing business processes in the organization, aiming at reducing time and cost in the elaboration of the particular model. In this context, the objective of this work is to develop a reference model of the Production Scheduling (PS) processes, an important module of production planning and control (PPC). The research methodology used in this work was divided into the following stages: study of PS and business process modeling, definition of reference model processes, choice of methodology and process modeling tool, development of reference model and prototype of the software and, finally, analysis of results. The modeling notation used was the BPMN, since it is considered a standard language in the field of process modeling. The prototype was developed through the Delphi interface in order to apply the model to support the implementation of business management programs. As results, from a formal documentation, the model proved to be a useful mechanism in the understanding of the processes raised and appropriate in the support to the implantation of production management tools

    Behavioral Finance: A Different View in the State of Rio de Janeiro

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    The objective of this work is to present the consolidation of foreign reflections of a new branch in the financial theory, behavioral finance, that it aims at to adhere to the psychological aspects and the sociological ones of the individuals in the process of taking of decision at the moment to carry through an investment, as well as its applications through the incorporation of evidences on the irrationality of the investor. This new segment has as objective the revision and the improvement of the economic-financial model used currently. Through this study it was verified presence of the effect of super valuation of the assets and the effect disposal, as well as of aversion to the risk, since in the occurred economic crisis in 2008 middle a bigger index in the closing of companies was evidenced, and a minor in the opening of companies in the state of Rio De Janeiro. The association to the behavioral finance in such a way provides the agreement of the psychological process that motivates the investments, assisting in the construction of a model of more adequate taking of decision, how much in the act of contract of its administrators who will have to possess abilities adequate psychological techniques and in intention to prevent cognitive bias as reliable excess. The regression for being static got errors in its forecast high thus was not an incisive method, being able to be applied the forecast of demand of products, not obtaining success thus in this model

    Oil and Gas on the Brazilian Coast

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    The study of behavioral finance is characterized by analyzing the volatility of financial markets, however, in a contemporary view, one can also apply it in other fields such as commerce and factories, and its dislike to be able to invest or not its financial capital . The objective of this work is to present foreign reflections on a new branch in financial theory, Behavioral Finance, which aims to adhere the psychological and sociological aspects of the individuals in the decision making process at the time of making an investment, as well as their applications through incorporation evidence of the investor\u27s irrationality. This new segment aims to review and improve the current economic-financial model. The association with behavioral finances provides both the understanding of the psychological process that motivates the investments, helping in the construction of a more adequate decision-making model, and in the hiring of its managers who must possess adequate technical and psychological skills in order to avoid cognitive bias as overconfidence

    Proposal of a Reference Model in BPMN Notation for an MRP System

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    Companies are progressively investing in practices aimed at improving the quality of management, with the main purpose of enabling them to operate competitively in the present market. For this, it is necessary to document the activities and information of the existing business processes in the organization, aiming at reducing time and cost in the elaboration of the particular model. In this context, the objective of this work is to develop a reference model of the Manufacturing Resource Planning (MRP) processes, an important module of production planning and control (PPC). The research methodology used in this work was divided into the following stages: study of MRP and business process modeling, definition of reference model processes, choice of methodology and process modeling tool, development of reference model and prototype of the software and, finally, analysis of results. The modeling notation used was the BPMN, since it is considered a standard language in the field of process modeling. The prototype was developed through the Delphi interface in order to apply the model to support the implementation of business management programs. As results, from a formal documentation, the model proved to be a useful mechanism in the understanding of the processes raised and appropriate in the support to the implantation of production management tools

    Dormência múltipla e efeito maternal na germinação de sementes de Miconia ferruginata (Melastomataceae), Serra de Caldas Novas, Goiás, Brasil

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    Species with mostly asexual reproduction are interesting subjects for germination studies since variation would be more easily linked to environmental factors. Miconia ferruginata DC. is an apomictic treelet in Brazilian cerrado areas on rocky outcrops. Germination of seeds collected from individuals occurring in the Serra de Caldas Novas State Park, Goiás, was studied in three experiments under controlled conditions. Germination characteristics differed among individuals and were correlated with altitude and soil Al content. Seeds from plants growing at lower altitudes, with lower soil aluminium content, presented malformed seeds with absence of embryo which rendered lower, but better synchronized germination. The nested analysis showed that from the total variance, 78.14% for germinability, 54.56% for uncertainty of the germination process, and 68.30% for the quantity of seeds without embryo was attributed to the altitudinal effect. Individuals nested within altitude contributed up to 16.93% for the total variance. It means that there is low variability among individuals of the same altitude and high variability among individuals from different points of the slope, making clear that for the studied population the environmental effect is stronger than the genetic component to determine the seed quality. The testa of the seeds provides a mechanical dormancy which seems to be associated also with phenolic compounds, which help to disperse germination through time. Photoblastism was also registered for seeds of this species.Espécies com reprodução principalmente assexuada são interessantes para estudos de germinação, uma vez que a variação pode ser mais facilmente associada a fatores ambientais. Miconia ferruginata DC. é um arbusto apomítico de cerrado rupestre brasileiro. A germinação de sementes coletadas no Parque Estadual da Serra de Caldas Novas, Goiás foi estudada em três experimentos sob condições de laboratório. O processo de germinação diferiu entre os indivíduos, correlacionando-se com altitude e teor de Al do solo. Sementes oriundas de plantas crescendo nas menores altitudes, com menor teor de alumínio no solo, apresentaram sementes mal formadas, com ausência de embrião, resultando em baixa germinabilidade, mas maior sincronia de germinação. A análise hierárquica mostrou que 78,14% da variabilidade na germinabilidade, 54,56% na incerteza e 68,30% na quantidade de sementes sem embrião foram atribuídos ao efeito altitudinal. Indivíduos agrupados dentro de altitude contribuíram até 16,93% para a variância total. Isto significa que há baixa variabilidade entre indivíduos da mesma altitude e alta variabilidade entre indivíduos de diferentes pontos da Serra, indicando que para a população estudada o efeito ambiental é mais forte do que o componente genético para determinar a qualidade das sementes. A testa das sementes propiciou dormência mecânica que parece estar associada com a presença de compostos fenólicos, o que ajuda a dispersar a germinação no tempo. Fotoblastismo também foi registrado para sementes dessa espécie.92105Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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