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721.
Following the argument that increasing mobility has scattered consumption throughout Sweden’s regions, this study investigates how individuals’ consumption choices are influenced by official heritage. It argues that individuals’ everyday routines highlight the role played by heritage in socio-economic regional change, challenging traditional planning systems and altering individuals’ relationships with their environments, leading to new values being placed on official heritage. This argument was tested using interviews and questionnaires in Mariefred, Sweden, and demonstrates that official heritage plays multiple and contrasting roles, including the use of heritage as an attempt to reconcile opposing principles such as progress/development and tradition/conservation. 相似文献
722.
Gabriela E. Soares Henrique E. Borges Rogério M. Gomes Gustavo M. Zeferino Ant?nio P. Braga 《Natural computing》2012,11(3):405-413
Based on the Theory of Neuronal Group Selection (TNGS), we have investigated the emergence of synchronicity in a network composed of spiking neurons via genetic algorithm. The TNGS establishes that a neuronal group is the most basic unit in the cortical area of the brain and, as a rule, it is not formed by a single neuron, but by a cluster of tightly coupled neural cells which fire and oscillate in synchrony at a predefined frequency. Thus, this paper describes a method of tuning the parameters of the Izhikevich spiking neuron model through genetic algorithm in order to enable the self-organization of the neural network. Computational experiments were performed considering a network composed of neurons of the same type and another composed of neurons of different types. 相似文献
723.
Lucelia Borges Joaquin A. Morón-VillarreyesMarcelo G. Montes D’Oca Paulo Cesar Abreu 《Biomass & bioenergy》2011,35(10):4449-4454
The aim of this study was to investigate the possible interference of anionic and cationic flocculants in the lipid extraction and fatty acid profiles of two species of marine microalgae: Nannochloropsis oculata and Thalassiosira weissflogii. Cells were grown in batch cultures (f/2 medium, salinity of 28, temperature of 20 °C, light intensity of 40 ??mol photons m-2 s-1 and 12/12 h L/D photoperiod) and concentrated using sodium hydroxide (control), sodium hydroxide and the anionic polyacrylamide flocculant Magnafloc® LT-25 (APF treatment) and sodium hydroxide plus the cationic polyacrylamide flocculant Flopam® (CPF treatment). There were no statistically significant differences among treatments with respect to lipid extraction for both species. However, N. oculata which presented higher percentages of C16:0, C16:1 and C20:5 fatty acids showed an increase of C14:0 and a decrease of C20:5 with the use of anionic flocculant. Additionally, T. weissflogii which had high percentages of C16:0, C16:1, C16:3 and C20:5, showed a decrease of C18:0 and C18:1n9c when both flocculants were used and a small decrease of C16:0 in the APF treatment. The results indicate that the choice of flocculant should be based on the level of saturation desirable, i.e., if the goal is to produce more stable biodiesel, with low percentage unsaturated fatty acids, then anionic flocculants should be used. On the other hand, if the aim is to produce unsaturated fatty acids for commercial uses in the pharmacy or food industries, then anionic polymers should be avoided. 相似文献
724.
Andrea Luiza de Oliveira Mariana Nascimento de Paula Jurandir Fernando Comar Vanessa Rodrigues Vilela Rosane Marina Peralta Adelar Bracht 《International journal of molecular sciences》2013,14(11):21858-21872
The fruit extracts of Citrus aurantium (bitter orange) are traditionally used as weight-loss products and as appetite suppressants. A component of these extracts is octopamine, which is an adrenergic agent. Weight-loss and adrenergic actions are always related to metabolic changes and this work was designed to investigate a possible action of octopamine on liver metabolism. The isolated perfused rat liver was used to measure catabolic and anabolic pathways and hemodynamics. Octopamine increased glycogenolysis, glycolysis, oxygen uptake, gluconeogenesis and the portal perfusion pressure. Octopamine also accelerated the oxidation of exogenous fatty acids (octanoate and oleate), as revealed by the increase in 14CO2 production derived from 14C labeled precursors. The changes in glycogenolysis, oxygen uptake and perfusion pressure were almost completely abolished by α1-adrenergic antagonists. The same changes were partly sensitive to the β-adrenergic antagonist propranolol. It can be concluded that octopamine accelerates both catabolic and anabolic processes in the liver via adrenergic stimulation. Acceleration of oxygen uptake under substrate-free perfusion conditions also means acceleration of the oxidation of endogenous fatty acids, which are derived from lipolysis. All these effects are compatible with an overall stimulating effect of octopamine on metabolism, which is compatible with its reported weight-loss effects in experimental animals. 相似文献
725.
726.
Sandra Borges Joana Barbosa Rute Camilo Ana Carvalheira Joana Silva Sérgio Sousa Ana M. Gomes Maria M. Pintado José P. Silva Paulo Costa Maria H. Amaral Paula Teixeira Ana C. Freitas 《International Journal of Food Science & Technology》2012,47(2):416-421
The effect of microencapsulation on the viability of Lactobacillus casei, L. paracasei, L. acidophilus Ki and Bifidobacterium animalis BB‐12 during exposure to lethal conditions (25% NaCl, pH 3.0 and 55–60 °C) was evaluated. Results demonstrated that survival of probiotic strains to the imposed lethal stress conditions was strain dependent. With the exception of exposure to 25% (w/v) NaCl, L. acidophilus Ki (free and encapsulated cells) demonstrated the highest survival rates through exposure to lethal conditions of temperature and pH. For this probiotic strain exposed to heat, microencapsulated cells expressed a higher heat tolerance at 55 °C than free cells. For the other tested bacteria, in general, encapsulation had no positive effect on survival through the tested lethal conditions. 相似文献
727.
728.
A model is proposed for simulation of an industrial Claus unit with a straight-through configuration and two catalytic reactors. Process design evaluation based on deterministic calculations does not take into account the uncertainties associated with the input variables. The probabilistic simulation method was applied in the Claus model to obtain an impression of how some of these inaccuracies influence plant performance. The application was tested experimentally to confirm its validity, then used for control purposes. 相似文献
729.
A high resolution simple swept source for OCT measurements is presented. Low skew frequency domain triggering via electronic processing allowed resolutions of one FFT bin for a single reflection. The high resolution capability was demonstrated in a system containing ~10 ?m spaced interfaces. 相似文献
730.
The general purpose of this work is a thermodynamic study of non‐metallic inclusions in the CC tundish for SAE 8620 steel. Specific purposes are: (1) Obtaining the phases formed and their composition in inclusions by applying computational thermodynamics for SAE 8620 steel; (2) Establishing conditions of steel composition for the improvement of SAE 8620 castability, including the plant validation in terms of the castability index. Thermodynamic studies were performed with the commercial software FactSage and databases. Simulations were carried out by the global chemical composition of SAE 8620 steel in the CC tundish, resulting in both steel composition and non‐metallic inclusions (oxides and sulphides) at the desired temperature. Furthermore, results showed both different solid oxides and liquid phase formation in inclusions by varying calcium content in the steel. Thus, it was possible to determine the inclusion composition as a function of aluminium and calcium content of SAE 8620 steel, and moreover, to establish a range of calcium content in which the inclusions are predominantly formed by liquid phase. In addition, the percentages of liquid and solid phase in inclusions, as well as, oxide compositions could be calculated. 相似文献