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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11817
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Item Cocoa byproduct in diets for dairy heifers(Revista Brasileira de Zootecnia, 2018) Figueiredo, Mércia Regina Pereira de; Saliba, Eloisa de Oliveira Simões; Barbosa, Geraldo Sérgio Senra Carneiro; Lopes, Fernando César Ferraz; Silva, Filipe Aguiar e; Silva, Cecília Ribeiro da Mota e; Nunes, Andressa Nathalie; Figueiredo, Meliza Cristina Pereira deThis study was conducted to evaluate the effect of substituting Tifton 85 hay (Cynodon sp. cv. Tifton 85) with levels of cocoa (Theobroma cacao) byproduct (0, 8, 16, and 24%, diet dry matter basis) in the diet of 16 Holstein × Gir heifers with an average body weight of 363.0±27.7 kg on their nutrient intake, digestibility, and protein balance. The experimental period was 17 days, and the sample collection period was five days. There was no effect of cocoa byproduct on nutrient intake. However, the byproduct affected the digestibility of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber, all of which decreased as the level of inclusion of the byproduct in the diet was increased. Nitrogen balance was negatively affected by the inclusion of 24% cocoa byproduct. It is recommended to use cocoa byproduct up to the level of 16% to replace Tifton 85 grass hay in diets for dairy heifers.Item Magnetic carbon nanofiber networks as support for ionic liquid based catalyst(Catalysis Letters, 2015-02) Tristão, Juliana C.; Nassor, Evelisy C. O.; Oliveira, Henrique S.; Moura, Flávia C. C.; Santos, Eduardo N. dos; Lago, Rochel M.; Araujo, Maria HelenaIn this work, the ionic liquid (IL) 1-hexyl-3-methyl-imidazolium bromide (HMIm.Br) containing Pd suspended nanoparticles was supported on a nanostructured magnetically recoverable carbon nanofiber network. The magnetic material was prepared by a simple reaction of ethanol directly with a nanostructured hematite. SEM, XRD, Mössbauer, Raman, TG/DTA, BET surface area and magnetization analyses suggested that the network is based on carbon nanofibers with carbon coated magnetic Fe nanoparticles. These magnetic networks offer a high exposed carbon fiber area, which has a good interaction with the IL to form a thin layer. Preliminary studies with a Pd dispersed in supported IL as catalyst for the hydrogenation of 1,5-cyclooctadiene showed a membrane effect, which leads to an important increase on the selective hydrogenation of 1,5-cyclooctadiene to cyclooctene.Item Application of Lactobacillus paracasei LPC02 and lactulose as a potential symbiotic system in the manufacture of dry-fermented sausage(LWT, 2019-03) Torres Filho, Robledo de Almeida; Coelho, Samira Reis; Lima, Ítalo Abreu; Martins, Maurilio Lopes; Benevenuto Júnior, Augusto Aloísio; Ramos, Alcinéia de Lemos Souza; Ramos, Eduardo MendesThe purpose of this study was to evaluate how the incorporation of the probiotic culture Lactobacillus paracasei and the prebiotic lactulose in dry-fermented sausage affects the technological, microbiological and sensorial characteristics of the products. Four formulations were analyzed: CONT (without prebiotic or probiotic); PREB (with 2% lactulose); PROB (with 108 CFU/g of L. paracasei); and SYMB (with 2% lactulose and 108 CFU/g of L. paracasei). The functional ingredients did not affect (P > 0.05) the water activity, pH, moisture, acidity and lactic acid bacteria counts during ripening process. Lower (P < 0.05) residual nitrite values were observed in sausages added with probiotic (7.20 ± 1.32 mg NO2/kg) than in the other treatments (11.38 ± 3.21 mg NO2/kg). The proximate composition and the sensorial attributes were not affected (P > 0.05) by the treatments. A mean concentration of 2.16 ± 0.39% of lactulose was observed in PREB and SYMB sausages and a count of 7.59 ± 0.37 log CFU/g of L. paracasei was observe in PROB and SYMB sausages. The incorporation of lactulose and L. paracasei into this traditional meat product resulted in a potential probiotic and symbiotic salami, adding additional nutritional benefits for the consumer.Item Classification of auditory selective attention using spatial coherence and modular attention index(Computer Methods and Programs in Biomedicine, 2018-11) Souza, Ana Paula de; Soares, Quenaz B.; Felix, Leonardo B.; Mendes, Eduardo M. A. M.Brain-Computer Interfaces (BCIs) based on auditory selective attention have been receiving much attention because i) they are useful for completely paralyzed users since they do not require muscular effort or gaze and ii) focusing attention is a natural human ability. Several techniques - such as recently developed Spatial Coherence (SC) - have been proposed in order to optimize the BCI procedure. Thus, this work aims at investigating and comparing two strategies based on spatial coherence detection: contralateral and modular classifiers. The latter is a new method using modular attention index. The new classifier was developed to implement an auditory BCI where a volunteer makes binary choices using selective attention under the amplitude-modulated tones stimulation. Contralateral and modular classifiers were applied to the electroencephalogram (EEG) recorded from 144 subjects under the BCI protocol. The best set of parameters (carriers of the stimulus, channels and trials of signal) for this BCI was investigated taking into consideration the hit rate and the information transfer rate. The best result obtained using the modular classifier was a hit rate of 91.67% and information transfer rate of 6.74 bits/min using 0.5 kHz/4.0 kHz as stimuli and three windows (5.10 sec of EEG signal). These results were obtained with five electrodes (C3, P3, F8, P4, O2) using exhaustive search to identify regions with greater coherence.The modular classifier - using electroencephalogram channels from the central, frontal, occipital and parietal areas - improves the performance of auditory BCIs based on selective attention.Item Quantum properties of a which-way detector(Physica Scripta, 2015) Rossi Jr, R; Oliveira Filho, J. S.; Nemes, M. C.We explore quantum properties of a which-way detector using three versions of an idealized two slit arrangement. First, we derive complementarity relations for the detector; second, we show how the 'experiment' may be altered in such a way that using a single-position measurement on the screen, we can obtain quantum erasure. Finally, we show how to construct a superposition of 'wave' and 'particle' components.Item Rheological properties of selected Brazilian honeys as a function of temperature and soluble solid concentration(International Journal of Food Properties, 2017) Silva, Vanelle Maria da; Torres Filho, Robledo de Almeida; Resende, Jaime Vilela deSteady shear (η) and complex viscosities (η*) are important rheological properties of honeys. In this study, the effects of temperature and total soluble solids (TSS) concentration on these properties in 40 different Brazilian honeys were investigated. All honeys showed liquid-like behaviour at the temperatures and mechanical spectra tested and, except for the orange blossom and multi-southeast samples, respected the Cox-Merz rule. It was found that η varied between 147.3 Pa s and 0.35 Pa s, and η* between 151.33 Pa s and 0.42 Pa s, at 10°C and 60°C, respectively. Four experimental models (Arrhenius, Williams-Landel-Ferry (WLF), Vogel–Tamman–Fulcher (VTF), and power law) were used to evaluate the effect of temperature on η and η*. The Arrhenius model was the most appropriate for estimation of η of all honeys and η* of some. WLF was the most appropriate for predicting η* of the orange blossom, multi-southeast, and multi-southern honeys. Increase in temperature and decrease in TSS concentration lowered these values. The effect of TSS concentration on η and η* at different temperatures could be appropriately described by the power law and exponential models. Simplified models were proposed to determine the η and η* from the combined effect of both factors, which presented R2 of 0.9540 and 0.9334, and RMSE of 8.00 and 10.44, respectively. Thus, all models obtained in this study provide important tools towards the proper industrialisation of honeys and honey-based products.Item Rossby numbers of fully convective and partially convective stars(Proceedings of the International Astronomical Union, 2016-10) Landin, Natália R.; Mendes, Luiz T. S.In this work, we investigate the stellar magnetic activity in the theoretical point of view, through the use of stellar structure and evolution models. We present theoretical values of convective turnover times and Rossby numbers for low-mass stars, calculated with the ATON stellar structure and evolution code. We concentrate our analysis on fully convective and partially convective stars motivated by recent observations of X-ray emission of slowly rotating fully convective stars, which suggest that the presence of a tachocline is not a central key for magnetic fields generation. We investigate the behavior of the convective turnover time evolution, as well as its radial profile inside the star. A discussion about the location where the convective turnover time is calculated in the stellar interior is also addressed. Our theoretical results are compared to observational data from low-mass stars.Item Comparison of different criteria used to categorize technological quality of pork(Ciência Rural, 2016-12) Cazedey, Henrique Pereira; Torres Filho, Robledo de Almeida; Fontes, Paulo Rogério; Ramos, Alcinéia de Lemos Souza; Ramos, Eduardo MendesPork may be classified into quality categories according to its color, texture and exudation, though no international consensus criterion has been reached yet. Thus, the aim of the present paper was to examine the relation between important meat quality traits, evaluating pork quality classification of a same data by different criteria proposed in the literature. In 60 pork loins (Longissimus thoracis muscle), initial pH (pH45min) and R-value were evaluated after 45min post mortem between the 9th and 10th ribs, and ultimate pH (pH24h), objective color and water-holding capacity were evaluated 24h post mortem in two 2.54cm thick steaks cut between the 9th and 11th ribs to be classified into PSE (pale, soft and exudative), RSE (reddish-pink, soft and exudative), RFN (reddish-pink, firm and non-exudative) or DFD (dark, firm and dry) quality. Frequency distributions of quality categories differed (P<0.001) among criteria, which resulted in large variations: 3 to 68% PSE; 0 to 73% RSE; 5 to 68% RFN; 0 to 22% DFD; and 0 to 33% unclassified samples. A same sample may be classified into different quality categories according to the criterion utilized, which results in large variations in frequency distributions and also in quality attributes. Therefore, the classification of pork quality depends on the adopted criterion, which indicated the need for international standardization, so that pork quality can be determined efficiently and effectively.Item Characterization of the consumer market and motivations for the consumption of craft beer(British Food Journal, 2018) Carvalho, Naiara Barbosa; Minim, Luis Antonio; Nascimento, Moysés; Ferreira, Gustavo Henrique de Castro; Minim, Valéria Paula RodriguesThe purpose of this paper is to determine the demographic characteristics and habits of craft beer consumers, as well as to identify the motivational factors for consumption.Data were collected through questionnaires applied to 316 Brazilian craft beer consumers, and results were evaluated descriptively and by multivariate statistics.The results of the survey revealed that there is a growing market segment with different buying habits and behaviors compared to traditional beer consumers. Demographically, it was found that these consumers are an attractive part of the beer market in terms of age, schooling and, more importantly, in terms of income, factors that indicate the probability of continued growth in the sector.The research was limited to craft beer consumers in the metropolitan region of Belo Horizonte/MG, Brazil.The results obtained are important, as they can help new craft breweries, as well as help established industry managers to create strategies related to marketing four Ps in order to increase the consumption of its products, with competitive advantages to the market.This research presents the characteristics of the consumers of craft beer, a market segment in evident rise in Brazil, about which there are few studies. In addition, it provides valuable information to both the new beverage manufacturers as well as to the already established entrepreneurs in the market so that they can increase the consumption of their products in a strategic way.Item Parametric competition in non-autonomous Hamiltonian systems(Optics Communications, 2014-11-15) Souza, L. A. M.; Faria, J. G. P.; Nemes, M. C.In this work we use the formalism of chord functions (i.e. characteristic functions) to analytically solve quadratic non-autonomous Hamiltonians coupled to a reservoir composed by an infinity set of oscillators, with Gaussian initial state. We analytically obtain a solution for the characteristic function under dissipation, and therefore for the determinant of the covariance matrix and the von Neumann entropy, where the latter is the physical quantity of interest. We study in details two examples that are known to show dynamical squeezing and instability effects: the inverted harmonic oscillator and an oscillator with time dependent frequency. We show that it will appear in both cases a clear competition between instability and dissipation. If the dissipation is small when compared to the instability, the squeezing generation is dominant and one can see an increasing in the von Neumann entropy. When the dissipation is large enough, the dynamical squeezing generation in one of the quadratures is retained, thence the growth in the von Neumann entropy is contained.
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