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Immobilization of enzymes of agroindustrial interest on hydroxyapatite nanoparticles: β-glucosidase, xylase and phytase
(Universidade Federal de São Carlos, 2020-03-10) Coutinho, Thamara Carvalho; Farinas, Cristiane Sanchez; https://lattes.cnpq.br/9933650905615452; https://lattes.cnpq.br/5153535377625755
Industrial processes are increasingly requiring environmentally sustainable technologies and the use of enzymes is relevant due to the selectivity and specificity of these biocatalysts. However, the application of soluble enzymes in catalytic processes is often impracticable due to the high cost of these biocatalysts and the catalytic instability under severe physical-chemical process conditions. In this sense, the immobilization of enzymes guarantees the reuse of these biomolecules and often improves their stability. Among the supports used as immobilizing agents, nanoparticles have been increasingly studied due to the possibility of creating structures with high surface area to adsorb proteins and also to demonstrate low resistance to mass transfer, thus ensuring good accessibility of the catalyst to the substrate. Hydroxyapatite (HA) is a solid inorganic potential for immobilizing enzymes, since it is non-toxic, has good chemical and physical resistance, good ability to interact with proteins and can be synthesized in the form of nanoparticles; however, it has been little explored as a support for enzymatic immobilization. Given this context, the objective of this research was to evaluate the immobilization of the enzymes β-glucosidase, xylanase and phytase on hydroxyapatite nanoparticles (HA), as a strategy to improve the catalytic efficiency and stability of these enzymes. These enzymes have wide application in different sectors of the agribusiness, such as biofuels, food, animal feed and drugs. For this, HA nanoparticles were first characterized in order to understand their composition, size, morphology and surface area. Then, a systematic study of the immobilization of these enzymes in HA was carried out. The biochemical aspects of enzymatic immobilization were investigated, such as the physicochemical conditions of adsorption and desorption, that helps to understand the type of chemical interaction between support and enzyme. Changes in enzymatic activity profile, thermo-stability, conversion capacity during enzymatic hydrolysis and reuse of these biomolecules were also evaluated. The results obtained showed that the β-glucosidase, phytase and xylanase enzymes were efficiently immobilized on the HA nanoparticles using a simple and fast adsorption protocol, which occur mainly through coordination interactions between the Ca2+ sites of the HA with the carboxylic acids (COO-) of the enzyme amino acids. The biochemical behavior of the enzymes in the presence of HA was evaluated under different physicochemical conditions of adsorption and desorption (pH and ionic strength), indicating a strong and highly stable interaction between enzymes and support, with immobilization yields close to 100% and recovered activities in the range of 70-100%. For β-glucosidase it was possible to recycle the immobilized enzyme and retain 70% of the initial activity during at least 10 hydrolysis cycles. For phytase, the immobilized enzyme showed broader activity profile as to pH and temperature, and higher stability at high temperatures than free enzyme, whose improvement in its properties suggested the potential of applying the immobilized form of phytase in animal feed. For xylanase, the immobilized enzyme demonstrated greater affinity for the HA support that was modified with Cu2+ ions, promoting chelation interaction with enzyme amino acids, generating derivatives with maintenance of their catalytic activity and with activity profile similar to that of the free enzyme. Finally, the three enzymes were immobilized on HA magnetic nanoparticles (synthesized with cobalt ferrite, CoFe2O4), demonstrating excellent recovery capacity from the reaction medium through the application of a magnetic field. The results obtained showed the potential of HA to act as a support for enzyme immobilization, creating derivatives with promising industrial applications, which can improve processes and make them more sustainable.
Extração de palavras e mapeamento com estímulos visuais ao longo de tentativas ambíguas em paralelo
(Universidade Federal de São Carlos, 2020-03-10) Souza, Rodrigo Dal Ben; Hay, Jessica Sari Fleming; Souza, Débora de Hollanda; https://lattes.cnpq.br/3640676759708745; https://lattes.cnpq.br/7424970384206600
Learning an oral language presents several challenges, two of which are: extracting words from continuous speech and mapping them to referents. Statistical cues (e.g., prosody, phonotactical probability) are an important source of information to overcome such challenges. Evidence suggests that the higher or lower probability of a syllable being followed by another one (transitional probability) can be indicative of word boundaries in continuous speech. Additionally, segmentation and mapping processes can occur sequentially and simultaneously as a result of tracking the co-occurrence between words and its referents. Nonetheless, there is still a limited number of studies investigating simultaneous processes of word segmentation based on transitional probability and mapping based on cooccurrences across ambiguous trials (when more than one word and one referent is presented). The present investigation aims to answer the following question: can words be simultaneously segmented from continuous speech and mapped to referents across ambiguous trials? Three studies were conducted to investigate this question. The first study, with nine experiments, investigated whether pseudowords (previously selected) could be extracted from continuous speech based on their transitional probability. Brazilian-Portuguese and English adult speakers participated. Results indicated that words can be segmented, but only when other statistical cues, such as the phonotactical probabilities, are controlled. The second study, with two experiments, investigated whether segmented words from the languages used in the first study could be mapped to abstract pictures during cross-situational word learning tasks. Brazilian-Portuguese adult speakers participated. Results suggest that words can be mapped and that performance improves when the task is repeated. Finally, the third study, with two experiments, investigated whether extraction and mapping over ambiguous trials can occur in parallel. Brazilian-Portuguese and English adult speakers participated. Results suggest that these processes can occur together, at the same time, and that accuracy rates in the parallel task are higher than accuracy rates in individual tasks (Studies 1 and 2). By combining transitional probability and the cooccurrence of stimuli across ambiguous trials, the present investigation helps to advance the current understanding of the role played by linguistic regularities in language learning. Additionally, this work inaugurated this line of investigation in Brazil, which can motivate future investigations of the topic.
Classificação de retornos utilizando dados de alta frequência no mercado de bitcoins
(Universidade Federal de São Carlos, 2020-03-10) Emílio, João Mateus Arcolini; Fernandes, Ricardo Augusto Souza; https://lattes.cnpq.br/0880243208789454; https://lattes.cnpq.br/5077328227235621
In the cryptocurrency market, Bitcoin stands out as the most accepted traded in the world. However, due to its high volatility, the prediction of price behaviors, in special, the trend classification, becomes a challenge and valuable to investors. In this sense, in recent years, some studies have been proposed based on machine learning techniques to classify reliable trading signals from the Bitcoin return series. Thus, the present work explores Bitcoin's trend behaviors, seeking to classify its returns using high-frequency data from limit order book in terms of US dollar (BTCUSD) and euro (BTCEUR). The proposed methodology seeks to accurately predict returns, creating opportunities that better support trading strategies. Therefore, from the Bitcoin historical series, technical indicators (commonly used in financial markets), market variables and the own series of returns for different time intervals were extracted. It is worth mentioning that the data have a frequency of at most one second for each update of the entire order book, thus characterizing the high-frequency. Subsequently, these data are submitted to the inputs of trend classifiers based on Artificial Neural Networks and XGBoost, which were trained and validated in three months of trading, from January to March 2019, composing approximately 5 million market updates for each currency base. In a first analysis, the behaviors of the models for each base currency were observed, it is possible to note that the market for BTCUSD proves to be more efficient related to BTCEUR. Consequently, the machine learning models obtained more reliable and stable results over time for BTCUSD. Based on this initial result, sought to validate the predictive models for different training and validation configurations. In this second analysis, it was noted that the trend classification is more accurate for short intervals (between 1 and 3 minutes) in both base currencies, which is justified due to the high volatility in Bitcoin prices in short intervals. In a third analysis, it was observed that as we increased the number of training days for classifiers, in some cases, was noted a gradual loss in classification (between 1% and 2%). Still, in a fourth analysis, one-vs.-rest was applied to each trend behavior, there is a considerable performance increase in the classification in relation to the base case (between 1% and 7%)
Arcabouço biorreabsorvível de poli(L-co-D,L ácido láctico-co-trimetileno carbonato) cultivado com célula-tronco mesenquimal direcionada à regeneração óssea: estudo in vitro e in vivo
(Universidade Federal de São Carlos, 2020-03-10) Asami, Jessica; Duek, Eliana Aparecida de Rezende; https://lattes.cnpq.br/4147198882685212; https://lattes.cnpq.br/1956436970361884
Degenerative and bones inflammatory problems represents almost half of chronic diseases developed on people older than 50 years old around the world, leading to problems of prolonged pain and physical limitation. Its prevalence increases with age and life style, therefore, with elderly population growth, these cases have been increasing too. These problems resolution, usually demand surgeries which involve implant and bone graft. Even with these therapeutic solution success, some inconvenient have been appearing, because of the fact implants are susceptible to infections, and because of grafts can lead to severe pain, local tissue death, and immunological rejection. Aiming to solve these limitations, Tissue engineering have appeared as an promising field of bone wound repair and reconstruction, through tridimensional porous matrix development, usually designated as scaffolds. Associated to these structures, are osteoprogenitors cells and growth factors, which lead to new bone tissue growth, through stimulation of ability of natural tissue regeneration of patient. Aiming this important clinical gap, the biomaterial Poly(L-co-D,L lactic acid- co-Trimethylene Carbonate) (PLDLA-TMC) presents advantageous features to the medical field, mainly when related to stem cells, due to immunemodeling activities of this cells. Therefore, in this essay it was seeding in a PLDLA-TMC 3D scaffold with different pores sizes (300 e 600 µm) for proliferation and ostegenic differentiation. In vivo assay were used 36 Wistar rats and were made a cranial bone defect with 8 mm diameter, separeted in 3 groups: negative control, group with PLDLA-TMC and group with PLDLA-TMC+MSC, in periods of 8 and 12 weeks. The results in vitro assay obtained for analysis by Laser Scanning Confocal Microscopy (LSCM) showed that PLDLA-TMC 3D scaffolds with 600 µm pore size, when compared the sacaffold of 300 µm pore size, favored the adherence and cell growth, and mainly, presented osteoinductive characteristic, which means that the material itself inducted cellular differentiation. The scaffolds implants of PLDLA-TMC with MSC, through histological and microCT analisys, showed better results in the period of 12 weeks, obtainning less inflammatory process and greater regeneration of bone tissue.
Democracia eleitoral e o papel dos partidos políticos na estruturação do voto - um caso Africano: Moçambique (1994-2014)
(Universidade Federal de São Carlos, 2020-03-10) Terenciano, Fidel; Braga, Maria do Socorro Sousa; https://lattes.cnpq.br/2311094074614215; https://lattes.cnpq.br/5517594589421771
This thesis is part of the range of recent studies of political and electoral development in Africa (since 2000), and seeks to highlight the simultaneous relationship between the role of political parties and voters in structuring an electoral democracy. It was in this context that this thesis aims to analyze the role of political parties in structuring the vote in Mozambique. Starting from the use of a methodology that complements the historical-institutional approach and the political culture, with the use of official electoral data, the most important results of the thesis, show that there is a tendency for political parties in Mozambique, after 20 years of the implementation of the democracy, structure the vote, through their areas of dominance and belonging. It is noteworthy that, in these areas (a. Gaza, Cabo Delgado, Maputo; b. Nampula, Sofala, Zambézia), since the period of the civil war, they have always been in favor of the Frelimo government and Renamo, respectively. Henceforth, despite a notoriety in terms of the structure of voting in Mozambique, there is an inverse tendency for the stability of abstention levels to grow from election to election in almost all areas of Mozambique, despite the increase in investment in socio-economic development programs, as public policies on education, health, improvements in HDI and GDP, did not reflect in the same proportionality with the increase in political and electoral engagement.
Acessibilidade para pessoas com mobilidade reduzida no Centro Histórico da Estância Turística de Itu (São Paulo - Brasil)
(Universidade Federal de São Carlos, 2020-03-10) Ozelin, Thaís; Santos, Maria Helena Mattos Barbosa dos; https://lattes.cnpq.br/3419477918842537; https://lattes.cnpq.br/2615485979104940
The accessibility for people with reduced mobility was researched in interface with tourism in the Itu Tourist City, in the State of São Paulo, aiming to verify the development in the treatment of the issue of accessibility in the context of historic centers and the feasibility of accessibility for people with reduced mobility in historical and cultural attractions. To achieve the objective of this research, an investigation was carried out with documentary survey and bibliographic review, in addition to the use of exploratory techniques. For this, a Check List was applied regarding the adequacy of space and enterprise to accessibility standards, present in the Manual of Technical Accessibility Instructions to Support the Architectural Project (SMPED, 2008) elaborated by the city of São Paulo with the objective of visualizing in a clearer and more aims at accessibility conditions, in addition to photographic records, including with the perspective of proposing possible improvements in the city’s Tourist Center. Special attention was given to attractions such as Cruzeiro de São Francisco, Casa Imperial (Casa Capelli), Fábrica São Luiz, 19th century Architectural Ensemble, Republican Museum, Church of Nossa Senhora da Candelária of the Itu Tourist City, in relation to accessibility for people with reduced mobility. Despite the enormous challenges posed to public and private institutions with regard to the application of accessibility norms and guidelines, nationally implemented and disseminated it is necessary to emphasize that there is ample research effort on the part of national and international teaching and research institutions international, in order to offer solutions that harmonize the confrontation of these challenges and the safeguarding of historical memories and the heritage of the communities. At the end of this work, it was concluded that accessibility for all is supported by a broad concept in Brazilian legislation, which seeks greater inclusion, giving an opportunity to participate in tourism, however, a large part of the laws are ignored or unknown from society, municipal administration and also by people with reduced mobility.
Biomarcadores bioquímicos em fígado de girinos de rãs-touro, Lithobates catesbeianus, como indicadores biológicos de contaminação aquática
(Universidade Federal de São Carlos, 2020-03-10) Fernandes, Isabela Ferreira; Carvalho, Cleoni dos Santos; https://lattes.cnpq.br/7233550271936621; https://lattes.cnpq.br/7473518658996350
Various contaminants can affect the aquatic ecosystem and the organisms that live in it and can interfere with their physiological processes, as they accumulate in different tissues. Therefore, the evaluation of the effects of these contaminants on aquatic organisms contributes to the predictability of the action of different pollutants in this environment, generating information on mechanisms of adaptability to environmental stressors, as they are used as indicators of aquatic contamination. For this purpose, the experimental design consisted of exposing for 96 h bullfrog tadpoles, Lithobates catesbeianus, the water collected from two points (P1 and P2) of the Sorocaba River and in the dry (August and September) and rainy (March) periods. The following parameters were evaluated in the liver: protein concentration (metallothionein - MT, carbonyl proteins - PCO) and (lipid lipoperoxidation - OPL). In addition, the presence of metals, agrochemicals and drugs in the water and sediment at both points of the river were analyzed. In the analysis of water and sediment, the presence of agrochemicals and drugs was not detected; however, the presence of metals was verified at both points and in both periods. The presence of metals significantly increased MT and PCO in the liver of tadpoles exposed to water in P1 and P2 and in the rainy season, while in the dry period, the concentration of PCO and OLP significantly increased in the liver of tadpoles exposed to water from P1 and P2, respectively. These results indicate a picture of oxidative stress by the presence of metals in the water and suggests that these animals were able to alter the metabolic pathways for detoxification processes. Therefore, these results demonstrated that the proposed effect biomarkers can be good indicators of aquatic contamination in bullfrog tadpoles.
Equisingularidades de funções definidas em ICIS e IDS
(Universidade Federal de São Carlos, 2020-03-10) Carvalho, Rafaela Soares de; Tomazella, João Nivaldo; https://lattes.cnpq.br/0051564735964760; Okamoto, Bruna Oréfice; https://lattes.cnpq.br/6824383277098012; https://lattes.cnpq.br/5798367476258179
We study the equisingularity of a family of function germs $\{f_t\colon(X_t,0)\to (\mathbb{C},0)\}$, where $\{(X_t,0)\}$ is a family of $d$-dimensional isolated determinantal singularity. We define the $(d-1)$th polar multiplicity of the fibers $X_t\cap f_t^{-1}(0)$, $m_{d-1}(X_t\cap f_t^{-1}(0),0)$, and we present results relating the constancy of $m_{k}(X_t\cap f_t^{-1}(0),0)$ for $k=0,\ldots,d-1$ and $m_i(X_t,0)$ for $i=0,\ldots,d$ with the constancy of the Milnor number of $f_t$ and the Whitney equisingularity of the families $\{(X_t\cap f_t^{-1}(0),0)\}$ and $\{f_t\colon(X_t,0)\to (\mathbb{C},0)\}$. In the particular case where $\{(X_t,0)\}$ is a family of isolated complete intersection singularity we provide a condition to ensure the Whitney conditions in terms of the integral closure of the ideal defining the singular set of each member of family $\{f_t\colon(X_t,0)\to (\mathbb{C},0)\}$. We also relate the constancy of the Milnor number of $f_t$ with the strict integral closure of the module formed by the partial derivatives of the application that defines $X_t\cap f_t^{-1}(0)$.
Núcleo aléfico: um estudo de A máquina do mundo repensada de Haroldo de Campos
(Universidade Federal de São Carlos, 2020-03-10) Bomfim, Monalisa Medrado; Martha, Diana Junkes Bueno; https://lattes.cnpq.br/1857520068239671; https://lattes.cnpq.br/7171053176602826
This work proposes a critical analysis of the poem A máquina do mundo repensada, by Haroldo de Campos, published in 2000, composed in terza rima and structured in three cantos. The aim is to develop a reflection about the mystical and biblical elements present in Canto III, supported by literature theory, poetry criticism and the poet’s literary criticism, besides references about Kabbalah selected from the material available in the collection at Casa das Rosas: Centro de Referência Haroldo de Campos. The analysis starts from the hypothesis that the Aleph, letter and symbol from the jewish culture, is an image that moves rhizomatically in the poem, that is, it appears randomly along the poem. We intend to demonstrate with our reading that the alephic image dissimulates itself in other words, but it keeps exercising the symbolism inherent to the Aleph’s image. In this way, the objective of this work’s Chapter I is to recover the alephic images present in Canto III of the poem A máquina do mundo repensada (2004a). Chapter II aims to narrow the association between Haroldo de Campos and Kabbalah texts, circumscribing the work’s kabbalistic Universe. In order to do it, we focus on the analysis of the haroldian library books. The alephic nuclei located in Chapter I and the kabbalistic themes discussed in Chapter II guide the reading performed in Chapter III, in which Canto III of the poem A máquina do mundo repensada (2004a) is extensively analysed through Kabbalah bias. This analysis takes into consideration the theoretical apparatus of texts about Kabbalah and by Walter Benjamin (Infância berlinense: 1900 (2017) and Sobre o conceito de história (1987). Benjamin’s texts allow us to think about the relation between the poetic persona and the tradition, focusing on the Kabbalah tradition mobilized in the studied Canto.
Efeito da densidade e distância de plantas daninhas no desenvolvimento de mudas pré-brotadas (MPB) de cana-de-açúcar
(Universidade Federal de São Carlos, 2020-03-10) Schedenffeldt, Bruna Ferrari; Monquero, Patricia Andrea; https://lattes.cnpq.br/2766526793830455; https://lattes.cnpq.br/0040986288381186
Among the factors that limit the full expression of the productive potential of sugarcane, the interference caused by the lack of weed control stands out. Thus, the objective of this work was to evaluate how the density and distance of Ipomoea nil and Digitaria horizontalis influence the development of pre-sprouted seedlings (MPB) of the sugarcane variety IAC SP 95-5000. The experimental design, for each weed species, was completely randomized (DIC) in a 4 x 5 + 1 factorial scheme, with four weed densities coexisting with MPB (1, 2, 4 and 8 plants, equivalent to 10 , 20, 40 and 80 plants m-2), five distances from the MPB (2, 6, 12, 18 and 24 cm) and a control without the weed, with four repetitions. MPBs were transplanted in 30 L pots and weeds were sown. After the flowering of the weeds, height, leaf area, dry biomass of the aerial part and nutritional analysis of the MPB leaf tissue were evaluated. The MPB furthest from D. horizontalis and I. nil showed greater development. Regarding the leaf area, higher values were found when the plants were 24 cm away from the weeds. The density and distance between D. horizontalis and Ipomoea nil in relation to MPB were affected by competition for macro and micronutrients, especially at higher weed densities.