Efeito de variáveis de processo no tempo de fermentação e na concentração das dicetonas vicinais totais

Among the main challenges in the beer industrial production is the market supply at the lowest cost and high quality, in order to ensure the expectations of customers and. consumers The beer fermentation stage represents approximately 70% of the whole time necessary to its production, having a obligatoriness of strict process controls to avoid becoming bottleneck in beer production. This stage is responsible for the formation of a series of subproducts, which are responsible for the composition of aroma/bouquet existing in beer and some of these subproducts, if produced in larger quantities, they will confer unpleasant taste and odor to the final product. Among the subproducts formed during the fermentation stage, total vicinal diketones is the main component, since it is limiting for product transfusion to the subsequent steps, besides having a low perception threshold by the consumer and giving undesirable taste and odor. Due to the instability of main raw materials quality and also process controls during fermentation, the development of alternative forms of beer production without impacting on total fermentation time and final product quality is a great challenge to breweries. In this work, a prior acidification of the pasty yeast was carried out, utilizing for that phosphoric acid, food grade, reducing yeast pH of about 5.30 to 2.20 and altering its characteristic from flocculent to pulverulent during beer fermentation. An increase of six times was observed in amount of yeast cells in suspension in the second fermentation stage regarding to fermentations by yeast with no prior acidification. With alteration on two input variables, temperature curve and cell multiplication, which goal was to minimize the maximum values for diketones detected in the fermenter tank, a reduction was obtained from peak of formed diacetyl and consequently contributed to reduction in fermentation time and total process time. Several experiments were performed with those process changes in order to verify the influence on the total fermentation time and total vicinal diketones concentration at the end of fermentation. This experiment reached as the best production result a total fermentation time of 151 hours and total vicinal diketone concentration of 0.08 ppm. The mass of yeast in suspension in the second phase of fermentation increased from 2.45 x 106 to 16.38 x 106 cells/mL of yeast, which fact is key to a greater efficiency in reducing total vicinal diketones existing in the medium, confirming that the prior yeast acidification, as well as the control of temperature and yeast cell multiplication in fermentative process enhances the performance of diketones reduction and consequently reduce the total fermentation time with diketones concentration below the expected value (Max: 0.10 ppm)

Análise técnica e econômica do processo de obtenção de espaguetes com adição de farinha de trigo integral e farinha de linhaça

This work studies the fabrication of spaghetti through the process at high temperatures through the use of flour added to flour and flaxseed meal, with the aim of evaluating the final product quality and estimate the cost of production. The values of moisture, ash, protein, wet gluten, gluten index, falling number and grain of flour and mixtures to test to be the possible use in mass manufacturing and technological criteria for compliance with current legislation. Spaghetti noodles type were manufactured by adding 10% and 20% flour and 10% and 20% flaxseed meal with performance of physical-chemical, sensory and rheological properties of the products. Further analysis was performed on the product acceptance and estimation of production cost in order to create subsidies to enable the introduction of products with greater acceptance and economic viability in the market by the food industry. On the rheology of the product test was cooking the pasta, specifying the volume increase, cooking time and percentage of solid waste. In the sensory evaluation was carried out the triangular test of product differentiation with 50 trained judges and acceptance testing by a hedonic scale with evaluation of the aspects color, taste, smell and texture. In defining the sensory profile of the product was performed with ADQ 9 judges recruited and trained at the factory, using unstructured scale of 9 cm, assessing the attributes of flavor of wheat, flax flavor, consistency, texture of raw pasta, raw pasta color and color of cooked pasta. The greater acceptance of product quality was good and the pasta with 20% flour, 10% followed by the full product, 10% and 20% flaxseed characterized the average quality of the criterion of loss analysis of solids, together with mass full commercial testing. In assessing the estimated cost of production, the two products more technologically feasible and acceptable (20% whole and 10% flaxseed) were evaluated in high temperature processes. With total cost of R $ 4,872.5 / 1,000 kg and R $ 5,354.9 / 1,000 kg respectively, the difference was related to the addition of lower inputs and higher added value in the market, flour and flaxseed meal. The comparative analysis of cases was confirmed the reduction in production time (10h), more uniform product to the drying process at high temperature compared to conventional

Monitoramento em tempo real de processos fermentativos por espectroscopia no infravermelho próximo (NIRS)

A chemical process optimization and control is strongly correlated with the quantity of information can be obtained from the system. In biotechnological processes, where the transforming agent is a cell, many variables can interfere in the process, leading to changes in the microorganism metabolism and affecting the quantity and quality of final product. Therefore, the continuously monitoring of the variables that interfere in the bioprocess, is crucial to be able to act on certain variables of the system, keeping it under desirable operational conditions and control. In general, during a fermentation process, the analysis of important parameters such as substrate, product and cells concentration, is done off-line, requiring sampling, pretreatment and analytical procedures. Therefore, this steps require a significant run time and the use of high purity chemical reagents to be done. In order to implement a real time monitoring system for a benchtop bioreactor, these study was conducted in two steps: (i) The development of a software that presents a communication interface between bioreactor and computer based on data acquisition and process variables data recording, that are pH, temperature, dissolved oxygen, level, foam level, agitation frequency and the input setpoints of the operational parameters of the bioreactor control unit; (ii) The development of an analytical method using near-infrared spectroscopy (NIRS) in order to enable substrate, products and cells concentration monitoring during a fermentation process for ethanol production using the yeast Saccharomyces cerevisiae. Three fermentation runs were conducted (F1, F2 and F3) that were monitored by NIRS and subsequent sampling for analytical characterization. The data obtained were used for calibration and validation, where pre-treatments combined or not with smoothing filters were applied to spectrum data. The most satisfactory results were obtained when the calibration models were constructed from real samples of culture medium removed from the fermentation assays F1, F2 and F3, showing that the analytical method based on NIRS can be used as a fast and effective method to quantify cells, substrate and products concentration what enables the implementation of insitu real time monitoring of fermentation processes

Otimização do tempo e temperatura no processamento da gipsita oriunda dos cristalizadores da produção de sal para obter gesso de uso na construção civil

During the process of the salt production, the first the salt crystals formed are disposed of as industrial waste. This waste is formed basically by gypsum, composed of calcium sulfate dihydrate (CaSO4.2H2O), known as carago cru or malacacheta . After be submitted the process of calcination to produce gypsum (CaSO4.0,5H2O), can be made possible its application in cement industry. This work aims to optimize the time and temperature for the process of calcination of the gypsum (carago) for get beta plaster according to the specifications of the norms of civil construction. The experiments involved the chemical and mineralogical characterization of the gypsum (carago) from the crystallizers, and of the plaster that is produced in the salt industry located in Mossoró, through the following techniques: x-ray diffraction (XRD), x-ray fluorescence (FRX), thermogravimetric analysis (TG/DTG) and scanning electron microscopy (SEM) with EDS. For optimization of time and temperature of the process of calcination was used the planning three factorial with levels with response surfaces of compressive mechanical tests and setting time, according norms NBR-13207: Plasters for civil construction and x-ray diffraction of plasters (carago) beta obtained in calcination. The STATISTICA software 7.0 was used for the calculations to relate the experimental data for a statistical model. The process for optimization of calcination of gypsum (carago) occurred in the temperature range from 120° C to 160° C and the time in the range of 90 to 210 minutes in the oven at atmospheric pressure, it was found that with the increase of values of temperature of 160° C and time calcination of 210 minutes to get the results of tests of resistance to compression with values above 10 MPa which conform to the standard required (> 8.40) and that the X-ray diffractograms the predominance of the phase of hemidrato beta, getting a beta plaster of good quality and which is in accordance with the norms in force, giving a by-product of the salt industry employability in civil construction

Estimativa da evapotranspiração espacial em uma região semiárida utilizando sensoriamento remoto

With the need to deploy management and monitoring systems of natural resources in areas susceptible to environmental degradation, as is the case of semiarid regions, several works have been developed in order to find effective models and technically and economically viable. Therefore, this study aimed to estimate the daily actual evapotranspiration (ETr) through the application of the Surface Energy Balance Algorithm for Land (SEBAL), from remote sensing products, in a semiarid region, Seridó of the Rio Grande do Norte, and do the validation of these estimates using ETr values obtained by the Penman-Monteith (standard method of the Food and Agriculture Organization-FAO). The SEBAL is based on energy balance method, which allows obtaining the vertical latent heat flux (LE) with orbital images and, consequently, of the evapotranspiration through the difference of flows, also vertical, of heat in the soil (G), sensitive heat (H) and radiation balance (Rn). The study area includes the surrounding areas of the Dourado reservoir, located in the Currais Novos/RN city. For the implementation of the algorithm were used five images TM/Landsat-5. The work was divided in three chapters in order to facilitate a better discussion of each part of the SEBAL processing, distributed as follows: first chapter addressing the spatio-temporal variability of the biophysical variables; second chapter dealing with spatio-temporal distribution of instant and daily radiation balance; and the third chapter discussing the heart of the work, the daily actual evapotranspiration estimation and the validation than to the study area

Relações entre mídia e lazer:o capitalismo, os meios e a apropriação do tempo livre nas sociedades industrial e pós-industrial

This research aims to understand the relationship between media, capitalism and ownership of free time for leisure practices in industrial societies and postindustrial. Searching is thus a conceptual framework that takes into account the kind of ideology that naturalizes the relationship of leisure with the foundations of contemporary media, and the media only with leisure, forgetting their insertion in the labor and industrial relations in society. We intend to demonstrate that every mode of production, in the capitalist system, entails a mode of reproduction. Methodologically, this is a first approximation, from theoretical concerns already performed, constituting a theoretical research, bibliographic and descriptive character. The results of the text drives us to the conclusion that the work and leisure spheres tend to be less and less differentiated, since both remain as activities of product management with the same intellective protocols, based on information and communication technology, and that accordingly, the media favors an expansion of productive activity even during leisure time

Pressupostos ontológicos para se pensar a nova tecnologia: técnica, informação e ser e tempo

La recherche presentée, realisée sur le domaine de la méthaphysique, s´agit de rassembler des pressupositions pour une fondamentation ontologique de la technologie de l´Information, basé sur la philophie de Martin Heidegger; foncièrement, sur l´analytique existentiel du Dasein dans l´ouvrage Être et Temps. À partir de la pensée sur ce qui est aujourd´hui , il s´agit d´investiguer sur quels fondaments la Nouvelle Tecnologie se fut érigée de façon a que nous sommes engajés au projet de numérisation des étants que en même temps que destine l´homme a l´oubli de l´Être, l´offre la possibilité de transformation. Le rapport entre la question de l´Être et la question de la technique est analysé comme des chemins croisés et dans ce carrefour il devient possible penser ce qui est technique, ce qui est information pour Heidegger et de quel façon les modes existentiels du Dasein sont prêtes pour caractériser l ´homme au sein de la tecnologie de l´information. Par cette appropriation, il reste penser comment c´est possible l´ouverture d´une perspective de reconduction de l´homme à la vérité de l´Être. Finalement, la structuration des fondements rends possible la réflexion discursive général: avec qui nous nous ocuppons, comme nous sommes, dans quelle direction nous nous acheminons, les thèmes générales, respectivement, des trois chapitres. Les points d´investigation du premier chapitre son: a) La caractérisation précise du Dasein, appuyé sur des considerations de Benedito Nunes, Hans-Georg Gadamer, Jacques Derrida et Rüdiger Safränski; b) Le concept de technique et son essence chez Heidegger; c) la distinction entre technique et technologie, appuyé sur le pensée de J. Ellul, Michel Séris, Otto Pöggeler, Michel Haar, Dominique Janicaud; c) Le concept de cibernetique chez Heidegger et chez Norbert Wiener; d) La caractérisation preliminaire d´information, l´analyse étimologique e philosophique, l´avis de Heidegger te les théories de Rafael Capurro; f) L´Analyse du phénomène de la numérisation des étants, des considérations de Virilio, et l´analyse d´un concept de virtuel avec Henri Bergson et Gilles Deleuze. Dans le deuxième chapitre, l´analyse des existentiels du Dasein vers le sommaire des fondements de base pour la caractérisation de la technologie de l´information comme un problème philosophique. Finalement, aprés avoir presenté les concepts introdutoires que délimitent le questionement, suivi par les indications et pressupositions ontologiques trouvés sur Être et Temps, le troisième chapitre disserte sur le péril, ce qui sauve et la sérénité, les trois mots-clés de la pensée heideggerienne sur la technique que permettent l´approche conclusif de la question

Antecedentes histórico-filosóficos da problemática do tempo e do mal no freiheitsschrift de schelling: aproximações gnósticas

This thesis aims better understanding the relation between time and evil in Schelling s Freiheitsschrift, having its starting point in approximations from Gnosticism. For that purpose, before approaching that relation, it is reviewed (chapter I) the question of Gnosticism, a strain of thought essentially concerned with the problem of time and permeated by the belief in an evil nature of creation, and which is alleged to have significantly influenced certain ideas of Schelling. An evaluation of approximations between Gnosticism, gnosis and German thought follows (chapter II), as well as an evaluation of Schellingian aproximations to Gnosticism (chapter III). Then, the Freiheitsschrift is analysed as the text where Schelling, having taken hold of a very distinct appropriation of Gnosticism, goes beyond Kantian theodicy (chapter IV). Some interrogations about whether key ideas of Schellingian philosophy (about gnosis, creation, duality, time, and evil) are conceived in a way that is essentially different from that of historic Gnosticism, despite the much that has been said to the contrary, are then addressed (chapter V). The proposal of a Platonic-Plotinian key to the understanding of the relations between time and evil in the Freiheitsschrift comes next (chapter VI), and then gives way to the concluding remarks (chapter VII). We perceive that Gnosticism and Neoplatonism are systems of thought that sometimes converge, and that German thought is one of the places of this convergence. Notwithstanding this perception, it is possible to affirm that Schellingian thought, with its valorization of time and of a certain perception of evil, is essentially anti-gnostic, despite some contrary observations

Simetria de invariância de escala discreta, log-periodicidade e singularidades em tempo finito

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Efeito do tempo de repouso após fadiga induzida no desempenho neuromuscular do quadríceps femoral: ensaio clínico, controlado, randomizado, cego

Objective: To evaluate the effect of different resting periods, after induced muscle fatigue, in the quadriceps femoris neuromuscular performance, in healthy subjects. Methods: Sixty-four volunteers, of both genders, with an average of 21,8 ± 1,7 years and mean body mass index of 24,2 ± 3,7 Kg/m2 were randomly assigned into 4 groups: control group (was not induced fatigue); Experimental Group 1 (Exp. 1 1 minute of rest after fatigue); Experimental Group 3 (Exp. 3 3 minutes of rest after fatigue) and Experimental Group 5 (Exp. 5 5 minutes of rest after fatigue). The subjects were evaluated to the knee´s joint position sense (JPS), followed by 5 flexion-extension knee concentric isokinetic contractions at 60°/s, with concomitant recording of median frequency (Fmed) of rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM). Then they underwent a muscle fatigue protocol (30 flexion-extension knee concentric contractions at 60°/s) and were reevaluated on the isokinetic performance, Fmed and JPS. Blood lactate levels were measured before initial assessment, immediately after the fatigue protocol and 5 minutes after the end of the rest period. Results: The adoption of 3 minutes of rest was sufficient to restore the initial conditions for the peak torque normalized by body weight and the VL and VM Fmed. The joint position sense returned to its initial values with 1 minute rest. The lactate concentration remained high regardless of the adopted rest period. Conclusion: The use of 3-minute rest period is sufficient for the reestablishment of the neuromuscular parameters to the pre fatigue values.

No tempo dos brotos: juventude e diversão em Petrópolis e no Tirol (1945-1960)

The urban growth of Rio Grande do Norte capital gave his boldest step in the three earlier decades of the twentieth century seeking to catch up with foreign metropolis and also most developed Brazilian cities, for example, Rio de Janeiro. Novelties were such bulky that we can notice the rise of a new city which in many aspects superseded that one considered provincial by local intelligentsia. These urban interferences scratched city ground leaving indelible marks until the present day. The exacerbated growth of the city related to the 1940s, when Natal begins hosting the largest allied military base outside United States in the advent of World War II is important at a time when the city´s population doubled. The emergence of new leisure institutions, amidst already existing ones, continued marking the places as sociabilities and leisure permeated with meanings and representations are revealed. This work sought to know the sociability of Tirol and Petrópolis neighborhoods in Natal, in the period from 1945 to 1960, when the city witnesses the consolidation of a market increasingly focused on leisure and young people start to have a special participation in this process.

A escrita do tempo e a poética do espaço:história e espaço no livro Geografia do Brasil Holandês de Luís da Câmara Cascudo

In 1956, Luís da Câmara Cascudo published his book Geografia do Brasil Holandês. In this book, he studied and described a space - the Dutch Brazil - from a geographical and historical perspective. To do this, he articulated both perspectives from the point of view of his own reading of the History of Nordeste , establishing a dialogue with the historiographical tradition of the study of the Dutch Brazil in Pernambuco. When portraying the Dutch presence in Nordeste, Cascudo articulated a drama in which the Dutch would have their history described as a typically tragic plot, portrayed as if they were already condemned to failure in advance. To this tragedy he opposed a predominantly comic Portuguese plot, as if the Portuguese victory over the Dutch was as desirable as inevitable for the space of Nordeste . When narrating the clash between the Dutch and the Portuguese for the space of Nordeste , however, Cascudo ended up delineating his own place of speech, as a spokesperson for the identity of the potiguar space in opposition to the pernabucano space described by Freyre and Gonsalves de Mello. In this way, the space of Rio Grande do Norte would have its own identity, constructed from de Dutch absence and constituted from the Portuguese legacy contrarily to the space of Pernambuco, narrated from an articulation and a conciliation of the Flemish and Lusitan legacy, even though highlighting the latter. While the Dutch would had been a constant presence in the history of Pernambuco for Freyre and Gonsalves de Mello, they wouldn t have gone beyond legend in the space of Rio Grande do Norte, removed from its geography and erased from its history. When describing de geography of the potiguar space, therefore, Cascudo articulates the inexistence of the History of a time dominated by the Fleming with the search of a Portuguese space, trough the narration of its origins and constitution, as well as the registry of the characteristics of its legacy

Modelos de sobrevivência com fração de cura e omissão nas covariáveis

In this work we study the survival cure rate model proposed by Yakovlev (1993) that are considered in a competing risk setting. Covariates are introduced for modeling the cure rate and we allow some covariates to have missing values. We consider only the cases by which the missing covariates are categorical and implement the EM algorithm via the method of weights for maximum likelihood estimation. We present a Monte Carlo simulation experiment to compare the properties of the estimators based on this method with those estimators under the complete case scenario. We also evaluate, in this experiment, the impact in the parameter estimates when we increase the proportion of immune and censored individuals among the not immune one. We demonstrate the proposed methodology with a real data set involving the time until the graduation for the undergraduate course of Statistics of the Universidade Federal do Rio Grande do Norte

Estimação em modelos de tempo de falha acelerado para dados de sobrevivência correlacionados

We presented in this work two methods of estimation for accelerated failure time models with random e_ects to process grouped survival data. The _rst method, which is implemented in software SAS, by NLMIXED procedure, uses an adapted Gauss-Hermite quadrature to determine marginalized likelihood. The second method, implemented in the free software R, is based on the method of penalized likelihood to estimate the parameters of the model. In the _rst case we describe the main theoretical aspects and, in the second, we briey presented the approach adopted with a simulation study to investigate the performance of the method. We realized implement the models using actual data on the time of operation of oil wells from the Potiguar Basin (RN / CE).

Análise de resíduos em modelos de tempo de falha acelerado com efeito aleatório

We present residual analysis techniques to assess the fit of correlated survival data by Accelerated Failure Time Models (AFTM) with random effects. We propose an imputation procedure for censored observations and consider three types of residuals to evaluate different model characteristics. We illustrate the proposal with the analysis of AFTM with random effects to a real data set involving times between failures of oil well equipment