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991.
In buildings with heating, ventilation, and air-conditioning (HVAC), the Predicted Mean Vote index (PMV) was successful at predicting comfort conditions, whereas in naturally ventilated buildings, only adaptive models provide accurate predictions. On the other hand, permeable coverings can be considered as a passive control method of indoor conditions and, consequently, have implications in the perception of indoor air quality, local thermal comfort, and energy savings. These energy savings were measured in terms of the set point temperature established in accordance with adaptive methods. Problems appear when the adaptive model suggests the same neutral temperature for ambiences with the same indoor temperature but different relative humidities. In this paper, a new design of the PMV model is described to compare the neutral temperature to real indoor conditions. Results showed that this new PMV model tends to overestimate thermal neutralities but with a lower value than Fanger’s PMV index. On the other hand, this new PMV model considers indoor relative humidity, showing a clear differentiation of indoor ambiences in terms of it, unlike adaptive models. Finally, spaces with permeable coverings present indoor conditions closer to thermal neutrality, with corresponding energy savings. 相似文献
992.
Isabela Coelho Fernando Casare Danielle C. T. Pequito Gina Borghetti Ricardo K. Yamazaki Gleisson A. P. Brito Marcelo Kryczyk Luiz Claudio Fernandes Terezila M. Coimbra Ricardo Fernandez 《Lipids》2012,47(11):1031-1041
The objective of the present work was to study the renal function of healthy and tumor-bearing rats chronically supplemented with fish oil (FO), a source of n-3 polyunsaturated fatty acids. Weanling male rats were divided in two groups, one control (C) and another orally supplemented for 70?days with FO (1?g/kg body weight). After this time, half the animals of each group were injected in the right flank with a suspension of Walker 256 tumor cells (W and WFO). The W group had less proteinemia reflecting cachectic proteolysis, FO reversed this fact. Tumor weight gain was also reduced in WFO. Glomerular filtration rate (GFR) was not different in FO or W compared to C, but was higher in WFO. Renal plasma flow (RPF) was higher in the FO supplemented groups. The W group had lower plasma osmolality than the C group, but FO supplementation resulted in normalization of this parameter. Fractional sodium excretion (FENa+) of FO rats was similar to C. Proximal Na+ reabsorption, evaluated by lithium clearance, was similar among the groups. Urinary thromboxane B2 (TXB2) excretion was lower in the supplemented groups. The number of macrophages in renal tissue was higher in W compared to C rats, but was lower in WFO rats compared to W rats. In conclusion, FO supplementation resulted in less tumor growth and cachexia, and appeared to be renoprotective, as suggested by higher RPF and GFR. 相似文献
993.
Ana P. Aguiar Prudêncio Elane Schwinden Prudêncio Renata D.M. Castanho Amboni Aureanna N. Negrão Murakami Marcelo Maraschin José C. Cunha Petrus Paulo José Ogliari Rodrigo Santos Leite 《Food and Bioproducts Processing》2012,90(3):399-405
The goal of this study was to determine the best conditions to obtain the highest total polyphenol content from mate bark aqueous extract and investigate the phenolic composition and antioxidant activity of the concentrate obtained during nanofiltration. The Response Surface was employed to determine the optimum condition for extraction of polyphenolics from mate bark aqueous extract. The extract obtained using the best conditions (a temperature of 85 ± 5 °C and with extraction time of 1.5 min) contained approximately 1.6 mg/mL of chlorogenic acid equivalent, and was subjected to nanofiltration. The total polyphenol content values in the permeate and in the concentrate collected at different volume reduction factors (VRF of 1.5–6) were different from those detected in the optimized extract (unfiltered). The concentration of phenolic compounds and antioxidant activity increased when VRF was increased. The major compounds detected in optimized mate bark extract and its concentrates (VRF 4 and 6) were chlorogenic acid and epigallocatechin gallate, which can be related to the high antioxidant activity of mate bark aqueous extract. 相似文献
994.
Doreen Heerd Sirma Yegin Canan Tari Marcelo Fernandez-Lahore 《Food and Bioproducts Processing》2012,90(2):102-110
A comparative evaluation of three Aspergillus species according to their pectinase production in solid-state fermentation was performed. Solid-state fermentation offers several potential advantages for enzyme production by fungal strains. Utilization of agricultural by-products as low-cost substrates for microbial enzyme production resulted in an economical and promising process. The pectinolytic enzyme activities of two Aspergillus sojae strains were compared to a known producer, Aspergillus niger IMI 91881, and to A. sojae ATCC 20235, which was re-classified as Aspergillus oryzae. Evaluation of polymethylgalacturonase and polygalacturonase activity was performed as well as exo- vs. endo-enzyme activity in the crude pectinase enzyme-complex of the mentioned strains. Furthermore, a plate diffusion assay was applied to determine the presence and action of proteases in the crude extracts. A. sojae ATCC 20235 with highest polymethylgalacturonase activity and highest polygalacturonase activity both exo- and endo-enzyme activity, is a promising candidate for industrial pectinase production, a group of enzymes with high commercial value, in solid-state fermentation processes. Beside the enzymatic assays a protein profile of each strain is given by SDS-PAGE electrophoresis and in addition species-specific zymograms for pectinolytic enzymes were observed, revealing the differences in protein pattern of the A. sojae strains to the re-classified A. oryzae. 相似文献
995.
996.
Armando García Villegas Miguel A. Ocampo Enrique Saldivar‐Guerra Beatriz García‐Gaitán Eduardo Vivaldo‐Lima Gabriel Luna‐Barcenas 《应用聚合物科学杂志》2010,115(3):1289-1295
In this work, we propose a modified frontal polymerization method to build a uniform reaction front by gradually immersing the reacting mixture in a thermal bath. This scheme allows uniform materials to be obtained with nearly constant molecular weights and polydispersities and a low residual monomer concentration. A comparative study of the molecular weight distributions of poly(methyl methacrylate)s obtained by bulk polymerization, frontal polymerization, and frontal polymerization with the proposed gradual immersion is presented. Samples obtained by these methods show that materials obtained by bulk polymerization and by frontal polymerization are less uniform than those obtained by frontal polymerization with gradual immersion in a thermal bath. The obtained uniformity is directly related to a stabilizing effect of the reaction front by the gradual immersion of the reactor in a constant‐temperature bath and to a reduction in the reaction rate promoted by a moderate transfer agent concentration. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
997.
Marcelo Ramalho Amora Marcelo E. Pacheco Diana C. S. Azevedo Clio L. Cavalcante F. Murilo T. Luna 《化学工程与技术》2019,42(5):1018-1026
Industrial spent catalysts taken from different beds of industrial lube oil hydrotreating reactors were investigated in a pilot plant. Experiments to quantify the catalytic activity loss for hydrodesulfurization, hydrodenitrogenation, and aromatic hydrogenation reactions were carried out using an industrial feedstock under operational conditions similar to the industrial ones. Characterization of the spent catalysts was performed to demonstrate the relative influence of different possible deactivation causes. Depending on the position of the catalyst inside the industrial reactor, different deactivation causes were evaluated. At the top of the reactor, poisoning by silicon, arsenic, and iron was the main cause, while at the bottom, coke deposition was predominant. 相似文献
998.
Citation studies have become an important tool for understanding scientific communication processes, as they enable the identification of several characteristics of information-retrieval behavior. This study seeks to analyze citation behavior using two popular ethnobotany articles, and our analysis is guided by the following question: when an author references a work, is he pointing out the work??s theoretical contribution, or is bias a factor in citing this reference? Citation analysis reveals an interesting phenomenon, as the majority of citing texts do not consider the theoretical contributions made by the articles cited. Two possible conclusions can be drawn from this scenario: (1) citing authors read the original texts that they cite only superficially, and (2) the works cited are not read by the vast majority of people who reference them. Thus, it is clear that even with sufficient access to reference texts; ethnobotanical studies highlight elements less relevant to the research and reproduce discussions in a non-reflective manner. 相似文献
999.
1000.
Shirley Kuhnen Juliana Bernardi Ogliari Paulo Fernando Dias Elisangela Fabiana Boffo Isabel Correia Antônio Gilberto Ferreira Ivonne Delgadillo Marcelo Maraschin 《International Journal of Food Science & Technology》2010,45(8):1673-1681
This work aims at discriminating flours of 26 maize landraces from southern Brazil, by using the Attenuated Total Reflection Fourier Transform Infrared (ATR‐FTIR) spectroscopy and chemometrics (principal components analysis – PCA). PCA applied to the FTIR spectra in the 3‐600 (whole spectrum) and 1650–1500 cm?1 (fingerprint region of proteins) spectral windows clearly discriminated the Amarelão landrace. Quantitative and semi‐qualitative analysis of proteins showed a wide range among the fractions, mainly of prolamine (13.47–28.43 g Kg?1) and glutelin (5.57–30.98 g Kg?1) contents. Pixurum 6, Pixurum 5, and MPA1 landraces are of superior nutritional value for their albumin, globulin, and glutelin contents. PCA of the spectral dataset in the fingerprint region to carbohydrates (1200–950 and 1065–950 cm?1) also including commercial standards of amylose and amylopectin was able in separating the Moroti genotype, which grouped with the amylopectin standard. Thus, ATR‐FTIR and PCA showed to be useful tools for the quick screening and discrimination of maize with distinct chemical composition. 相似文献