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101.
102.
Discoloration process modeling by neural network 总被引:1,自引:0,他引:1
Oswaldo Luiz Cobra Guimares Marta Heloisa dos Reis Chagas Darcy Nunes Villela Filho Adriano Francisco Siqueira Hlcio Jos Izrio Filho Henrique Otvio Queiroz de Aquino Messias Borges Silva 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2008,140(1-3):71-76
The photo-oxidation of acid orange 52 dye was performed in the presence of H2O2, utilizing UV light, aiming the discoloration process modeling and the process variable influence characterization. The discoloration process was modeled by the use of feedforward neural network. Each sample was characterized by five independent variables (dye concentration, pH, hydrogen peroxide volume, temperature and time of operation) and a dependent variable (absorbance). The neural model has also provided, through Garson Partition coefficients and the Pertubation method, the independent variable influence order determination. The results indicated that the time of operation was the predominant variable and reaction mean temperature was the lesser influent variable. The neural model obtained presented coefficients of correlation on the order 0.98, for sets of trainability, validation and testing, indicating the power of prediction of the model and its character of generalization. 相似文献
103.
On the basis of two cases of sub-adventitial traumatic rupture of the left renal artery, as well as data from the literature, the authors indicate the relative poverty of clinical signs of traumatic rupture of the renal arteries. They stress the value of early intravenous pyelography in lumbar trauma, with immediate arteriography in the presence of a non-functioning kidney, making conservative surgery possible. 相似文献
104.
Marques AP Reis RL Hunt JA 《Journal of materials science. Materials in medicine》2005,16(11):1029-1043
Leukocyte adhesion to biomaterials has long been recognised as a key element to determine their inflammatory potential. Results
regarding leukocyte adhesion and activation are contradictory in some aspects of the material's effect in determining these
events. It is clear that together with the wettability or hydrophilicity/hydrophobicity, the roughness of a substrate has
a major effect on leukocyte adhesion. Both the chemical and physical properties of a material influence the adsorbed proteins
layer which in turn determines the adhesion of cells.
In this work polymorphonuclear (PMN) cells and a mixed population of monocytes/macrophages and lymphocytes (mononuclear cells)
were cultured separately with a range of starch-based materials and composites with hydroxyapatite (HA). A combination of
both reflected light microscopy and scanning electron microscopy (SEM) was used in order to study the leukocyte morphology.
The quantification of the enzyme lactate dehydrogenase (LDH) was used to determine the number of viable cells adhered to the
polymers. Cell adhesion and activation was characterised by immunocytochemistry based on the expression of several adhesion
molecules, crucial in the progress of an inflammatory response.
This work supports previous in vitro studies with PMN and monocytes/macrophages, which demonstrated that there are several properties of the materials that can
influence and determine their biological response. From our study, monocytes/macrophages and lymphocytes adhere in similar
amounts to more hydrophobic (SPCL) and to moderately hydrophilic (SEVA-C) surfaces and do not preferentially adhere to rougher
substrates (SCA). Contrarily, more hydrophilic surfaces (SCA) induced higher PMN adhesion and lower activation. In addition,
the hydroxyapatite reinforcement induces changes in cell behaviour for some materials but not for others.
The observed response to starch-based biodegradable polymers was not significantly different from the control materials. Thus,
the results reported herein indicate the low potential of the starch-based biodegradable polymers to induce inflammation especially
the HA reinforced composite materials. 相似文献
105.
The concentrations of V, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, and Pb were measured in digestive gland (DG), branchial hearts (BH), gill (G), and muscle (M) of Octopus vulgaris Cuvier, 1797 caught in three fishing areas of the Portuguese coast, Viana do Castelo, Cascais, and Santa Luzia, for 2 years. The elemental concentrations measured for the different tissues were in accordance with values reported in the literature. The digestive gland presented high concentration levels of Fe, Cu, and Zn, while the branchial hearts showed elevated levels of V, Ni, Mo, as well as Fe and Cu. Significant variations in As, V, Cu, Mo, and Pb tissue concentrations were observed for animals originated from different sampling sites. Pb and As determined in the digestive gland and branchial hearts of animals from Cascais and Santa Luzia, can reflect local environmental characteristics. The variability observed in the elemental concentrations may be useful to further assess the species susceptibility to environmental conditions. 相似文献
106.
A journal-style record was used to construct several indices characterizing the socializing among 35 male (M) and 36 female (F) undergraduates. These variables were then related to Ss' independently rated physical attractiveness. The following major results were obtained: (a) Physical attractiveness was strongly related to the quantity of social interaction for Ms, positively with the opposite sex and negatively with the same sex; no significant pattern emerged for Fs. (b) For both sexes, particularly with opposite-sex interactions, satisfaction showed an increasing tendency over time to be positively correlated with attractiveness. (c) Fs with more variable attractiveness ratings were more likely to be satisfied with their socializing. (d) Physically attractive Ms tended to have more mutually initiated and fewer self- or other-initiated interactions with the opposite sex. (e) Attractive Ms spent more of their interactions conversing and less in activities; attractive Fs also reported a lesser proportion of task interactions and more prevalent dates/parties. Mediating mechanisms for these effects, notably including people's stereotypic beliefs about physical attractiveness, are also discussed. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Lucía Ramírez-Cárdenas Alda J. Leonel Neuza M.B. Costa Fernando P. Reis 《Food research international (Ottawa, Ont.)》2010,43(2):573-581
Zinc bioavailability was studied in five cultivars of beans (Phaseolus vulgaris, L): white (Ouro Branco), black (Diamante Negro), and brown (BRS Radiante, Pérola and Talismã) cooked with or without soaking water. The cooked bean flours or ZnCO3 were added to the test or control diets to provide 15 mg Zn/kg diet and were fed to weaning Wistar male rats for 42 days. Blood and femur were collected for analyses of plasma and erythrocyte Zn, bone weight and bone/dietary mineral ratio. Zinc bioavailability of Ouro Branco bean cooked with soaking water was higher than the other cultivars and similar to the control diet. Talismã without soaking water showed the lowest values for most of the parameters analyzed. Zinc bioavailability was not affected neither by the cooking process itself nor by the contents of phytate, tannins and dietary fiber, but it varied according to the bean cultivar and the phytate × calcium:zinc molar ratio. 相似文献
108.
109.
Marcia Marie Maru Marcia Maria Lucchese Cristiano Legnani Welber Gianini Quirino Andrea Balbo Isabele Bulhes Aranha Lílian Terezinha Costa Cecília Vilani Lídia gata de Sena Jailton Carreteiro Damasceno Talita dos Santos Cruz Leandro Reis Lidízio Rui Ferreira e Silva Ado Jorio Carlos Alberto Achete 《Fuel Processing Technology》2009,90(9):1175-1182
Compatibility of the new environmentally-friendly alternative of diesel engine fuels, biodiesel, with storage and engine part materials, is still an open issue. In this work, the interaction between three fuels (petroleum diesel and two types of biodiesel — soybean and sunflower) and two materials (carbon steel and high density polyethylene) used in storage and automotive tanks, is analyzed in detail. A wide set of characterization techniques was used to evaluate the changes in both solid and fluid materials, as weight change measurement, optical, scanning electron and atomic force (AFM) microscopies, Raman and FTIR spectroscopies, and differential scanning calorimetry. The AFM technique allowed detecting surface roughness and morphology changes in the metallic material following the trends in the weight losses. In the case of polymeric material, weight gain by fluid absorption occurred, being detected by the spectroscopic techniques. The biodiesel fuels underwent some ageing however this phenomenon did not affect the interaction between the biodiesel fuels and the substrates. The petrodiesel, which did not age, caused more significant degradation of the substrates. 相似文献
110.
Field experiments were carried out to measure concentration and concentration fluctuation distributions on the surfaces of a complex shaped building under different stability conditions and to investigate the dependence of these distributions on the averaging time. Meteorological conditions varied from neutral to unstable. The measurements were conducted for two different building orientations to the mean wind direction. Periods of 30 min were selected based on the mean wind direction being normal to either the long or the short building wall within ±10 degrees. For shorter averaging times, the selected concentrations corresponded to the 1, 3, 5, 10 or 15 min periods in which each detector was indicating the highest average within this 30 min period. Averaging time seems to influence more the values of these maximum mean concentrations under unstable conditions than under neutral conditions on all the building walls, while the influence of averaging time is weaker in the case of the wind impinging on the short building wall under neutral conditions. Averaging time seems to have a stronger influence on concentration fluctuation intensity under unstable conditions, while the influence of averaging time on concentration fluctuation intensity is similar for both building orientations investigated. A power law function was found to describe well the dependence of the concentration on averaging time for all examined cases. The absolute values of the power law exponent p measured on the building surface are often higher than the values presented in the literature for open terrain. 相似文献