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51.
52.
Carlos Eduardo de Ara jo Padilha S rgio Dantas de Oliveira J nior Domingos Fabiano de Santana Souza Jackson Ara jo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos 《中国化学工程学报》2017,25(5):652-657
A hybrid GMDH neural network model has been developed in order to predict the partition coefficients of invertase from Baker's yeast. ATPS experiments were carried out changing the molar average mass of PEG(1500–6000 Da), p H(4.0–7.0), percentage of PEG(10.0–20.0 w/w), percentage of MgSO_4(8.0–16.0 w/w), percentage of the cell homogenate(10.0–20.0 w/w) and the percentage of MnSO_4(0–5.0 w/w) added as cosolute. The network evaluation was carried out comparing the partition coefficients obtained from the hybrid GMDH neural network with the experimental data using different statistical metrics. The hybrid GMDH neural network model showed better fitting(AARD = 32.752%) as well as good generalization capacity of the partition coefficients of the ATPS than the original GMDH network approach and a BPANN model. Therefore hybrid GMDH neural network model appears as a powerful tool for predicting partition coefficients during downstream processing of biomolecules. 相似文献
53.
Miguel G. Cruz Bret W. Butler Domingos X. Viegas Pedro Palheiro 《Combustion and Flame》2011,(10):1970-1976
The present study is aimed at quantifying the flame radiosity vertical profile and gas temperature in moderate to high intensity spreading fires in shrubland fuels. We report on the results from 11 experimental fires conducted over a range of fire rate of spread and frontal fire intensity varying respectively between 0.04–0.35 m s−1 and 468–14,973 kW m−1. Flame radiosity, or radiant emissive power, and gas temperatures were measured with narrow angle radiometers and fine wire thermocouples located at three different heights in the flames, 0.6, 1.1 and 1.6 m above ground. Measured peak radiosity within the visual flame region (reaction zone and free flame) varied between 41 and 176 kW m−2. Measurements within the intermittent flame region above the visually estimated average flame height varied between 10 and 30 kW m−2. The flame vertical radiometric profile was characterized by a uniform area within the reaction zone and lower free flame, and a decrease in radiosity with height as the measurements approach the flame tip. 相似文献
54.
Effect of oxygen on aroma volatiles and quality of fresh-cut cantaloupe and honeydew melons 总被引:1,自引:0,他引:1
Ana L. Amaro John C. Beaulieu Casey C. Grimm Rebecca E. Stein Domingos P.F. Almeida 《Food chemistry》2012
Cantaloupe and honeydew melon cultivars were processed and stored under a high oxygen passive modified atmosphere packaging (MAP) or reduced oxygen controlled atmosphere (CA; 5 kPa O2 + 10 kPa CO2 and balance N2) for 14 days at 5 °C. Atmosphere did not affect softening rate or soluble solids content and had a negligible effect on colour. Volatile compounds known as flavour-important in melons were extracted using stir bar sorptive extraction (SBSE) and quantified via GC–MS. Acetate esters increased more in MAP than in CA. Non-acetate esters increased markedly in both cultivars and storage types. Alcohols were more abundant in honeydew than in cantaloupe. Aldehydes decreased during storage in both cultivars and storage types. Lower O2 availability under CA conditions likely suppressed some of the esters relevant to the aroma of fresh-cut melon. Results suggest that package O2 levels are more important in determining aroma than other quality attributes of fresh-cut melon, and high O2 levels may be required to reveal desirable aroma compounds. 相似文献
55.
Ana L Amaro Joana F Fundo Ana Oliveira John C Beaulieu Juan Pablo Fernández‐Trujillo Domingos PF Almeida 《Journal of the science of food and agriculture》2013,93(4):828-837
BACKGROUND: Orange‐fleshed cantaloupe melons have intense aroma and flavor but are very perishable during storage life. Fresh‐cut processing enhances ethylene‐mediated quality losses. Post‐cutting 1‐methylcyclopene (1‐MCP) application to fresh‐cut cantaloupe was evaluated for its effects on quality attributes, phytochemical content and aroma volatiles. RESULTS: Fresh‐cut cantaloupe (Cucumis melo var. cantalupensis ‘Fiesta’) cubes treated with 1.0 µL L?1 of 1‐MCP for 24 h at 5 °C, packaged in vented plastic clamshells and stored under normal atmosphere at 5 °C for 9 days, preserved their soluble solids, total phenolics, total carotenoids and β‐carotene contents, but significant softening occurred. A significant increase of non‐acetate esters and a decrease of aldehydes occurred during storage. Most quality attributes of fresh‐cut cantaloupe were unaffected by the treatment with 1‐MCP. 1‐MCP‐treated fresh‐cut cantaloupe accumulated higher levels of propyl acetate, 2‐methylbutyl acetate, methyl butanoate, methyl 2‐methyl butanoate, methyl hexanoate, 2‐methylbutyl alcohol and phenethyl alcohol, and lower levels of benzyl alcohol and heptanal than untreated controls. CONCLUSION: Post‐cutting treatment with 1‐MCP affected nine of the flavor‐important volatiles, particularly those derived from the amino acids isoleucine and phenylalanine, but had no practical effect on phytochemicals or other quality attributes. © 2012 Society of Chemical Industry 相似文献
56.
Budding process during the organogenesis of the ventral prostatic lobe in mongolian gerbil
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Bruno Domingos Azevedo Sanches Manoel Francisco Biancardi Fernanda Cristina Alcantara Dos Santos Rejane Maira GóEs PatríCia Simone Leite Vilamaior SebastiãO Roberto Taboga 《Microscopy research and technique》2014,77(6):458-466
The prostate is a mammalian gland that shows a complex process of organogenesis. Here, a morphological study to characterize the organogenesis of the ventral prostate lobe in male gerbils was conducted. The urogenital sinus (UGS) was dissected out and processed for paraffin embedding. Histological sections were subjected to cytochemical, immunofluorescence, immunohistochemical, and three‐dimensional reconstruction techniques. We found that the first ventral buds emerged from the ventral urethral epithelium between the days 20 and 21 of prenatal life, reaching the ventral mesenchymal pad and initiating the branching process on the first day of postnatal life. The buds presented a V‐shaped elongation, suggesting that the smooth muscle layer (SML) plays an important role during budding events. Indeed, whereas the androgen receptor (AR) was preferentially found in the UGS mesenchyme (UGM), estrogen receptor alpha (ERα) was localized in both the UGM and in the emerging buds. This study characterized the morphological aspects of the budding process in a different rodent from rat and mice, serving as a new model for future studies on developmental biology of the prostate. Microsc. Res. Tech. 77:458–466, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
57.
M. Helena Gomes Randolph M. Beaudry Domingos P.F. Almeida F. Xavier Malcata 《Journal of food engineering》2010
Respiration rates were measured in fresh-cut ‘Rocha’ pear (Pyrus communis L.) stored at four temperatures (0, 5, 10 and 15 °C) and with oxygen partial pressures ranging from 0 to 18 kPa. Respiratory quotient and ethanol production were used to determine the fermentation threshold. The oxygen concentration effect on the respiration rate was accurately described using Michaelis–Menten kinetics, without non-competitive inhibition by CO2, and the effect of temperature on the respiration rate was well modelled by exponential functions. The oxygen level at which respiration was half its maximum (apparent Km,O2) was similar to or only slightly greater than the fermentation threshold. The narrow range of oxygen between Km,O2 and the fermentation threshold, suggests that modified atmosphere packaging technology has a limited applicability toward extension of the shelf-life of fresh-cut ‘Rocha’ pear. 相似文献
58.
Ribeiro CA Padrós J Domingos FX Akaishi FM Pelletier E 《The Science of the total environment》2007,372(2-3):549-553
We previously reported that long-term (54 days), repeated intraperitoneal exposure to low doses of tributyltin (TBT; 0.3 mg/kg) inhibited the metabolic activation of co-administered benzo[a]pyrene (BaP; 3 mg/kg) in the Arctic charr (Salvelinus alpinus); BaP, in turn, stimulated the metabolism and/or excretion of TBT. Here, we report the results of histopathological examinations of liver, kidney and pseudobranch tissue samples originating from these same fish. The results revealed higher lesion incidences at all sampling time points (Days 8, 32 and 56) among BaP-exposed fish compared with fish exposed to either TBT alone or combined with BaP. The severity of lesions like necrosis was also higher in BaP-exposed fish. Moreover, hepatic basophilic foci were observed exclusively in fish exposed to BaP alone. Together, these results provide new evidences that TBT can antagonize BaP toxicity in fish exposed to both pollutants under controlled laboratory conditions. In contrast, BaP does not appear to provide protection against TBT toxicity. 相似文献
59.
Deise F. Xavier Francisco J. da Silva Lédo Domingos S. de Campos Paciullo Segundo Urquiaga Bruno J. R. Alves Robert M. Boddey 《Nutrient Cycling in Agroecosystems》2014,99(1-3):45-62
In the south-eastern region of Brazil there are millions of hectares of deforested, almost-treeless hillsides with sparse ground-cover of grasses of African origin. For the establishment of more productive pastures in these areas, silvopastoral systems (SPSs) have been recommended, and the objective of this study was to quantify the N fluxes in the soil/plant/animal systems as a means compare the sustainability of a SPS planted with legume trees (Acacia mangium and Mimosa artemisiana) and eucalyptus, compared to that of a grass-alone Brachiaria decumbens (BDH) pasture. The annual live weight gain of Zebu × Friesian heifers, assessed 5 years after pasture establishment, was significantly higher on the SPS than on the grass-alone pasture, at 205 and 177 kg head?1 year?1 respectively. The N deposited as animal excreta (38–49 kg ha?1 for BDH and SPS, respectively), especially urine, is considered to be much more susceptible to loss than N derived from decomposing plant litter, and was found to be much less than the N recycled though the grass litter (107 and 114 kg ha?1, respectively) in both systems. The extra N recycled in tree-leaf and grass litter increased this by 34 kg N ha?1 in the SPS and we conclude that this would contribute to sustain forage productivity. The added advantage of trees in the provision of shade for the animals and protection from soil erosion should further contribute to the long term sustainable productivity of this SPS. 相似文献
60.
Kasra Kardarian Tito Busani Inês Osório Helena Domingos Rui Igreja Ricardo Franco João Cortez 《Materials Chemistry and Physics》2014
The demand for conductive textiles is increasing, owing to the need for lightweight and flexible conductive materials for a variety of applications, including electromagnetic shielding of electronic equipment. Herein we propose a process that combines the in situ synthesis of silver nanoparticles at the textile fibre surface followed by sintering of the nanoparticles to obtain highly conductive fabrics. The formation of silver particles at the nanoscale allowed for sintering to be performed efficiently, at reduced temperature and time, bestowing fabrics with high conductivity and capability of shielding electromagnetic radiation. The nanoparticle synthesis method entailed the precipitation of 2.0 g L−1 silver nitrate and further reduction with citrate, with the formation of a deposit of silver nanoparticles at the fabric surface. The amount of silver deposited (up to 195 mg of silver per g of fabric) resulted in moderate electrical conductivity with sheet resistance of 803 Ω/sq. Upon sintering, this value decreased dramatically to 5.2 Ω/sq. The sintering process was monitored by SEM, which showed that sintering at 200 °C for 30 min resulted in maximal electrical conductivity with the lowest amount of silver deposited, while forming a homogenous surface. Fabrics submitted to these sintering conditions maintained their sheet resistance and shielding effectiveness values, even after eight washing cycles. 相似文献