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1.
24 18–40 yr olds performed a memory-scanning task (S. Sternberg, 1966, 1969) in which probe letters were displayed unilaterally or bilaterally after sets of 2, 4, or 6 letters were memorized. The mean response time (RT) to bilateral presentations was significantly longer than the mean RT to unilateral presentations, but the slope of the set-size function was not affected, suggesting that presenting stimuli bilaterally affected stages other than memory scanning. There were no significant visual-field effects in either the bilateral or unilateral conditions, suggesting that memory scanning is not a lateralized process. There was no evidence that bilateral presentation increased visual-field differences. This is not consistent with D. B. Boles' (1983, 1990) hypothesis that visual-field asymmetry effects are more pronounced with bilateral than with unilateral presentation of stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The aim of this study was to bring to the surface the strategic use of imitative processes in the context of a 2-route model: (a) direct imitation, used in reproducing new, meaningless actions, and (b) imitation based on stored semantic knowledge of familiar meaningful actions. Three experiments were carried out with healthy participants who reproduced meaningful and meaningless actions within an established time limit. The study investigated 3 factors that could potentially affect the selection of processes used for imitation: (a) the composition of the experimental list (blocked or mixed presentation), (b) the presence-absence of instructions (Experiments 1 and 2), and (c) the relative proportions of the stimuli (Experiment 3). Overall, the results suggest that each of these factors influences the selection of imitative strategies in healthy individuals with temporarily reduced capacities, as happens in the case of brain-damaged patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
In this paper, we propose neural network approach for multicriteria solid transportation problems(STP). First we suggest a neural network architecture to solve single-objective STP according to augmented Lagrange multiplier method. Due to the massive computing unit-neurons and parallel mechanism of neural network approach can solve the large scale problem efficiently and optimal solution can be got. Then we transform the original multicriteria problem into a single objective problem by global criteria method and adopt the neural network approach to solve it. By this way we can get the satisfactory solution of the original problem. The procedure and efficiency of this approach are shown with numerical simulations.  相似文献   
4.
Neural Network(NN) is well-known as one of powerful computing tools to solve optimization problems. Due to the massive computing unit-neurons and parallel mechanism of neural network approach we can solve the large-scale problem efficiently and optimal solution can be gotten. In this paper, we intoroduce improvement of the two-phase approach for solving fuzzy multiobjectve linear programming problem with both fuzzy objectives and constraints and we propose a new neural network technique for solving fuzzy multiobjective linear programming problems. The procedure and efficiency of this approach are shown with numerical simulations.  相似文献   
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6.
Increasing potassium intake ameliorates blood pressure (BP) and cardiovascular (CV) prognoses in the general population; therefore the World Health Organization recommends a high-potassium diet (90–120 mEq/day). Hyperkalaemia is a rare condition in healthy individuals due to the ability of the kidneys to effectively excrete dietary potassium load in urine, while an increase in serum K+ is prevalent in patients with chronic kidney disease (CKD). Hyperkalaemia prevalence increases in more advanced CKD stages, and is associated with a poor prognosis. This scenario generates controversy on the correct nutritional approach to hyperkalaemia in CKD patients, considering the unproven link between potassium intake and serum K+ levels. Another concern is that drug-induced hyperkalaemia leads to the down-titration or withdrawal of renin-angiotensin system inhibitors (RASI) and mineralocorticoids receptors antagonists (MRA) in patients with CKD, depriving these patients of central therapeutic interventions aimed at delaying CKD progression and decreasing CV mortality. The new K+-binder drugs (Patiromer and Sodium-Zirconium Cyclosilicate) have proven to be adequate and safe therapeutic options to control serum K+ in CKD patients, enabling RASI and MRA therapy, and possibly, a more liberal intake of fruit and vegetables.  相似文献   
7.
The non‐pathogenic dimorphic fission yeast, Schizosaccharomyces japonicus, could be a suitable model organism for investigation of the genetic background of mycelial growth, as it has a haploid chromosome set and its genome is sequenced. Since earlier results have suggested that its morphological transition required solid substrates, but molecular biological experiments would require hyphae production in a liquid medium, we wanted to find circumstances which would enable hyphae production in liquid media. Several external conditions were investigated, but the strongest inducer was fetal bovine serum (FBS). Its positive effect could be hampered by heat and was dependent on pH, temperature and concentration of the serum. Other protein‐containing compounds, such as peptone and bovine serum albumin or amino acids, proved to be ineffective or weak. Generally, the uninduced and induced mycelial growth of Sz. japonicus could be improved by lower external pH and higher temperature. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
8.
We have studied the role of flavin adenine dinucleotide (FAD) in the in vivo assembly of peroxisomal alcohol oxidase (AO) in the yeast Hansenula polymorpha. In previous studies, using a riboflavin (Rf) autotrophic mutant, an unequivocal judgement could not be made, since Rf-limitation led to a partial block of AO import in this mutant. This resulted in the accumulation of AO precursors in the cytosol where they remained separated from the putative peroxisomal AO assembly factors. In order to circumvent the peroxisomal membrane barrier, we have now studied AO assembly in a peroxisome-deficient/Rf-autotrophic double mutant (Δper1.rif1) of H. polymorpha. By sucrose density centrifugation and native gel electrophoresis, three conformations of AO were detected in crude extracts of Δper1.rif1 cells grown under Rf-limitation, namely active octameric AO and two inactive, monomeric forms. One of the latter forms lacked FAD; this form was barely detectable in extracts wild-type and Δper1 cells, but had accumulated in the cytosol of rif1 cells. The second form of monomeric AO contained FAD; this form was also present in Δper1 cells but absent/very low in wild-type and rif1 cells. In vivo only these FAD-containing monomers associate into the active, octameric protein. We conclude that in H. polymorpha FAD binding to the AO monomer is mediated by a yet unknown peroxisomal factor and represents the crucial and essential step to enable AO oligomerization; the actual octamerization and the eventual crystallization in peroxisomes most probably occurs spontaneously.  相似文献   
9.
The reductive removal of nitric oxide from flue gases by reaction with polyacrylonitrile-based active carbon fibres (PAN-ACF) activated with sulphuric acid has been studied at 423–632 K, using a circulating flow reactor. Nitric oxide (0.67 mmol) was completely removed via reduction with 1 g activated carbon under optimum conditions in 210 and 60 min at 423 and 623 K, respectively. N2 was formed as NO was removed. Some oxygen remained on the carbon surface at 423 K, but was desorbed as CO or CO2 on subsequent heating to 623 K. The bimolecular reaction of NO reduction over PAN-ACF, and the possible active sites of oxygen surface groups are discussed in the light of a kinetic study and a comparison of the fibre activation at different temperatures.  相似文献   
10.
Confocal laser scanning microscopy (CLSM) and low-field nuclear magnetic resonance (LF-NMR) relaxometry were combined to characterize microstructural changes and water distribution in fresh and cooked pork during an aging period of 14 days. At day 1 (24 h postmortem) a few muscle fibres, which appear swollen, were observed in both fresh and cooked meat. An identical microstructure was still apparent after 14 days, however, the number of muscle fibres showing distinguished characteristics was found to increase throughout the aging period. Hence, it was apparent that during aging the individual fibres swell and disintegrate at different rates. Development in water-holding capacity (WHC) was followed during the aging period using gravimetric methods, and an increase in the WHC in the fresh meat was observed, which resembled the amount of extramyofibrillar water measured by NMR relaxometry (T22 population). This was consistent with the CLSM images, as a substantial increase in the number of myofibrils that appeared swollen, capable of holding more water, was observed during aging. In the cooked meat the width of the T21c population, reflecting the myofibrillar water in the cooked meat, was seen to decrease during the entire storage period, which corresponds to the development of a more homogeneous structure. In the CLSM data a continuous degradation during the storage period was observed, which could resemble a shift to a more homogeneous structure. Comparison of CLSM of transverse sections of fresh and cooked pork revealed a pronounced shrinkage of muscle fibres upon cooking. This resulted in large gaps between the cooked muscle fibres, which also was visible as shrinkage at the level of the individual myofibrils. This pattern was also reflected in the NMR relaxation data. The cooking-induced shrinkage of the myofibrils occurred concomitantly with a decrease in the amount of intermyofibrillar water within the individual fibre and an increase in the larger extramyofibrillar spaces between fibres, i.e. water is expelled from the myofibrillar matrix upon cooking. Accordingly, the present study demonstrated that the use of CLSM together with NMR relaxometry can provide further information on the relationship between structural characteristics of meat and resultant water distribution.  相似文献   
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