Processamento de bebida funcional r base do yacon (Polymnia sonchifolia Poepping e Endlicher)

Orientadora: Lys Mary Bileski CândidoDissertaçao (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduaçao em Tecnologia de Alimentos. Defesa: Curitiba, 2004Inclui bibliografia e anexo

Optimization of chemical peeling of yacon roots (Polymnia sonchifolia Poepp.)

A full factorial design 2³ was used to evaluate the effect of process variables in chemical peeling of yacon roots, cultivated in Curitiba, State of Paraná. Eleven treatments, with three central points, were done in which they had been evaluated at three different levels of sodium hydroxide solution, % (g/100 mL) [6, 10, 14], temperature of the same solution, °C [70, 80, 90], and residence time in the sodium hydroxide solution, minutes [2, 4, 6]. All the studied variables had affected significantly (p<0.05) the yield of yacon roots subjected to chemical peeling. The variable that most affected the yield was the time of permanence in the sodium hydroxide solution. The mathematical model obtained for the yield (%) was good with R² aj = 0.8497, and non significant lack of fit (p=0.9312).Therefore, the model can be used for predictive purposes. In the central point a satisfactory yield (84% to 87%) with a high percentage of removed peel was obtained (96% to 98%) indicating that the treatment with 10% of sodium hydroxide solution, temperature of 80º C per 4 minutes can be used in the chemical peeling of yacon roots.Foi utilizado o delineamento fatorial completo 2³ para estudar o efeito das variáveis de processo no descascamento químico de raízes do yacon, cultivadas na região metropolitana de Curitiba, estado do Paraná. Foram realizados 11 experimentos, com três repetições no ponto central, nos quais foram avaliados em três níveis a concentração da solução de hidróxido de sódio, % (g/100 mL) [6, 10, 14], temperatura da solução de hidróxido de sódio, °C [70, 80, 90] e tempo de permanência na solução de hidróxido de sódio, minutos [2,4,6]. Todas as variáveis estudadas afetaram de forma significativa (p<0,05) o rendimento das raízes submetidas ao descascamento químico. A variável mais importante para o rendimento foi o tempo de permanência na solução de hidróxido de sódio. O modelo obtido para a resposta percentual de rendimento foi adequado, com R² aj = 0,8497 e com falta de ajuste não significativa (p = 0,9312), podendo ser utilizado para fins preditivos. No ponto central, foi obtido um rendimento satisfatório (84% a 87%) e elevado percentual de casca removida (96% a 98%), indicando que o tratamento com 10% de solução de hidróxido de sódio a temperatura de 80º C por 4 minutos, pode ser empregado no descascamento químico das raízes do yacon.1301130

Time-dependent Ginzburg-Landau Equation in the Nambu--Jona-Lasinio Model

We apply the closed time-path Green function formalism in the Nambu--Jona-Lasinio model. First of all, we use this formalism to obtain the well-known gap equation for the quark condensate in a stationary homogeneous system. We have also used this formalism to obtain the Ginzburg-Landau (GL) equation and the time-dependent Ginzburg-Landau (TDGL) equation for the chiral order parameter in an inhomogeneous system. In our derived GL and TDGL equations, there is no other parameters except for those in the original NJL model.Comment: 20 pages, no figures. Version to appear in Nuclear Physics

A comparison of body composition assessment methods in climbers: Which is better?

Objective To compare body composition estimations of field estimation methods: Durnin & Womersley anthropometry (DW-ANT), bioelectrical impedance analysis (BIA) and Deborah-Kerr anthropometry (DK-ANT) against dual-energy X-ray absorptiometry (DXA) in a male Chilean sport climbing sample. Methods 30 adult male climbers of different performance levels participated in the study. A DXA scan (Lunar Prodigy (R)) was used to determine fat mass, lean mass and total bone mineral content (BMC). Total muscle mass (MM, kg) was estimated through a validated prediction model. DW-ANT and BIA ("non-athletes" and "athletes" equations) were used to determinate fat mass percentage (FM %), while DK-ANT was utilized to estimate MM and BMC. Results A significant (p<0.01) inter-method difference was observed for all methods analyzed. When compared to DXA, DW-ANT and BIA underestimated FM% and DK-ANT overestimated MM and BMC (All p< 0.01). The inter-method differences was lower for DW-ANT. Discussion We found that body composition estimation in climbers is highly method dependent. If DXA is not available, DW-ANT for FM% has a lower bias of estimation than BIA in young male Chilean climbers. For MM and BMC, further studies are needed to compare and estimate the DK-ANT bias level. For both methods, correction equations for specific climbing population should be considered

Protons in near earth orbit

The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is parameterized by a power law. Below the geomagnetic cutoff a substantial second spectrum was observed concentrated at equatorial latitudes with a flux ~ 70 m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure

A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01

The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics experiment that will study cosmic rays in the $\sim 100 \mathrm{MeV}$ to $1 \mathrm{TeV}$ range and will be installed on the International Space Station (ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected $10^8$ cosmic ray triggers. Part of the \emph{Mir} space station was within the AMS-01 field of view during the four day \emph{Mir} docking phase of this flight. We have reconstructed an image of this part of the \emph{Mir} space station using secondary $\pi^-$ and $\mu^-$ emissions from primary cosmic rays interacting with \emph{Mir}. This is the first time this reconstruction was performed in AMS-01, and it is important for understanding potential backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor stylistic and grammer change

Building The Sugarcane Genome For Biotechnology And Identifying Evolutionary Trends

Background: Sugarcane is the source of sugar in all tropical and subtropical countries and is becoming increasingly important for bio-based fuels. However, its large (10 Gb), polyploid, complex genome has hindered genome based breeding efforts. Here we release the largest and most diverse set of sugarcane genome sequences to date, as part of an on-going initiative to provide a sugarcane genomic information resource, with the ultimate goal of producing a gold standard genome.Results: Three hundred and seventeen chiefly euchromatic BACs were sequenced. A reference set of one thousand four hundred manually-annotated protein-coding genes was generated. A small RNA collection and a RNA-seq library were used to explore expression patterns and the sRNA landscape. In the sucrose and starch metabolism pathway, 16 non-redundant enzyme-encoding genes were identified. 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A synteny analysis shows that the sugarcane genome has expanded relative to the sorghum genome, largely due to the presence of transposable elements and uncharacterized intergenic and intronic sequences.Conclusion: This release of sugarcane genomic sequences will advance our understanding of sugarcane genetics and contribute to the development of molecular tools for breeding purposes and gene discovery. © 2014 de Setta et al.; licensee BioMed Central Ltd.151European Commission: Agriculture and Rural Development: Sugar http://ec.europa.eu/agriculture/sugar/index_en.htmKellogg, E.A., Evolutionary history of the grasses (2001) Plant Physiol, 125, pp. 1198-1205Grivet, L., Arruda, P., Sugarcane genomics: depicting the complex genome of an important tropical crop (2001) Curr Opin Plant Biol, 5, pp. 122-127Piperidis, G., Piperidis, N., D'Hont, A., Molecular cytogenetic investigation of chromosome composition and transmission in sugarcane (2010) Mol Genet Genomics, 284, pp. 65-73D'Hont, A., 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The utility of the new generation of humanized mice to study HIV-1 infection: transmission, prevention, pathogenesis, and treatment

Substantial improvements have been made in recent years in the ability to engraft human cells and tissues into immunodeficient mice. The use of human hematopoietic stem cells (HSCs) leads to multi-lineage human hematopoiesis accompanied by production of a variety of human immune cell types. Population of murine primary and secondary lymphoid organs with human cells occurs, and long-term engraftment has been achieved. Engrafted cells are capable of producing human innate and adaptive immune responses, making these models the most physiologically relevant humanized animal models to date. New models have been successfully infected by a variety of strains of Human Immunodeficiency Virus Type 1 (HIV-1), accompanied by virus replication in lymphoid and non-lymphoid organs, including the gut-associated lymphoid tissue, the male and female reproductive tracts, and the brain. Multiple forms of virus-induced pathogenesis are present, and human T cell and antibody responses to HIV-1 are detected. These humanized mice are susceptible to a high rate of rectal and vaginal transmission of HIV-1 across an intact epithelium, indicating the potential to study vaccines and microbicides. Antiviral drugs, siRNAs, and hematopoietic stem cell gene therapy strategies have all been shown to be effective at reducing viral load and preventing or reversing helper T cell loss in humanized mice, indicating that they will serve as an important preclinical model to study new therapeutic modalities. HIV-1 has also been shown to evolve in response to selective pressures in humanized mice, thus showing that the model will be useful to study and/or predict viral evolution in response to drug or immune pressures. The purpose of this review is to summarize the findings reported to date on all new humanized mouse models (those transplanted with human HSCs) in regards to HIV-1 sexual transmission, pathogenesis, anti-HIV-1 immune responses, viral evolution, pre- and post-exposure prophylaxis, and gene therapeutic strategies

A model of quiescent tumour microregions for evaluating multicellular resistance to chemotherapeutic drugs

The quiescent cell population of tumours poses a barrier to the success of many cancer therapies. Most chemotherapeutic drugs target proliferating cells, but the growth fraction of many tumours is low. Based on the multicellular tumour spheroid model, a system was developed using human colon adenocarcinoma (DLD-1) cells to mimic the microenvironment of quiescent microregions of solid tumours. The quiescent tumour spheroids (TSQ) showed decreased expression of the proliferation marker Ki-67 and increased expression of the quiescence marker p27kip1 compared to proliferating spheroids (TSP). The quiescent status of the TSQ was confirmed by long-term growth assessment. The quiescence was completely reversible demonstrating that the TSQ retained the ability to proliferate and morphological assessment by light microscopy confirmed the absence of significant apoptosis. When the efficacy of widely used chemotherapeutic drugs was determined, vinblastine, doxorubicin, cisplatin and 5-fluorouracil (5-FU) all produced significant cell death in the TSP. However, while still effective, the potencies of doxorubicin and cisplatin were significantly reduced in TSQ. In contrast, 5-FU and vinblastine did not produce cell death in the TSQ. In summary, TSQ show considerable resistance to a panel of established chemotherapeutic agents and represent a useful model for evaluating the efficacy of drugs and other cancer therapies in quiescent tumours