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991.
Szmalec Arnaud; Verbruggen Frederick; Vandierendonck André; Kemps Eva 《Canadian Metallurgical Quarterly》2011,37(1):137
The current study examined the nature of the processes underlying working memory updating. In 4 experiments using the n-back paradigm, the authors demonstrate that continuous updating of items in working memory prevents strong binding of those items to their contexts in working memory, and hence leads to an increased susceptibility to proactive interference. Results of Experiments 1 and 2 show that this interference reflects a competition between a process that reveals the degree of familiarity of an item and a context-sensitive recollection process that depends on the strength of bindings in working memory. Experiment 3 further clarifies the origins of interference during updating by demonstrating that even items that are semantically related to the updated working memory contents but that have not been maintained in working memory before cause proactive interference. Finally, the results of Experiment 4 indicate that the occurrence of interference leads to top-down behavioral adjustments that prioritize recollection over familiarity assessment. The implications of these findings for the construct validity of the n-back task, for the control processes involved in working memory updating, and for the concept of executive control more generally are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Oliver Raabe Mieke Lorenz Frank Pallas Eva Weis Alfred Malina 《Datenschutz und Datensicherheit - DuD》2011,35(8):519-523
In den folgenden Thesen sind die wesentlichen Anmerkungen und Anregungen der Verfasser zum Datenschutz im Smart Grid und in der Elektromobilit?t zusammengefasst. Dem Dokument liegen Untersuchungen der Verfasser aus dem Dokument „Datenschutz im Smart Grid“, das im Rahmen der gemeinsamen Begleitforschung der F?rderprogramme „E-Energy — IKT-basiertes Energiesystem der Zukunft“ und „IKT für Elektromobilit?t“ entstanden ist, zugrunde. 相似文献
993.
Carotenoids are important antioxidants and valuable bioactive compounds contributing to the health benefits of different foods, and rose hips are known for high bioactive content. This study investigated the content of carotenoids and chlorophylls in hips from four rose species during the ripening period. Carotenoid content varied greatly between harvesting times, although species and year, and interactions between factors, also played an important role. Some carotenoids were identified only in hips of specific rose species. Some of the investigated compounds decreased (chlorophyll a) or increased (lycopene) consistently over the ripening period and could therefore be useful as maturity markers. An optimal content of total or specific carotenoids, e.g. for food products containing rose hips, might be obtained by proper choice of harvesting time and rose species. 相似文献
994.
Eva Kasparek Uwe Zencker Robert Scheidemann Holger Völzke Karsten Müller 《Computational Materials Science》2011,50(4):1353-1358
Proper predictions of the behaviour of shock absorber materials are of utmost importance in safety assessments for licensing casks for transport and storage of highly active waste. After having identified significant discrepancies between numerical results and the actual response of polyurethane foam limiters subjected to accidental scenarios, a new research project ENREA was established by BAM. A major objective is to enhance and to develop advanced material models intended to simulate limiters under impact loading. They should account for all major factors influencing the load–deformation relationship like temperature, strain rate and specific stress state. The corresponding test program, applicable plasticity models, the overall parameter identification strategy based on local and global optimization techniques as well as experimental and numerical results are presented here in particular for closed cell foams. 相似文献
995.
996.
Kumar E Bhatnagar A Ji M Jung W Lee SH Kim SJ Lee G Song H Choi JY Yang JS Jeon BH 《Water research》2009,43(2):490-498
This research was undertaken to evaluate the feasibility of granular ferric hydroxide (GFH) for fluoride removal from aqueous solutions. Batch experiments were performed to study the influence of various experimental parameters such as contact time (1 min-24 h), initial fluoride concentration (1-100 mg L−1), temperature (10 and 25 °C), pH (3-12) and the presence of competing anions on the adsorption of fluoride on GFH. Kinetic data revealed that the uptake rate of fluoride was rapid in the beginning and 95% adsorption was completed within 10 min and equilibrium was achieved within 60 min. The sorption process was well explained with pseudo-first-order and pore diffusion models. The maximum adsorption capacity of GFH for fluoride removal was 7.0 mg g−1. The adsorption was found to be an endothermic process and data conform to Langmuir model. The optimum fluoride removal was observed between pH ranges of 4-8. The fluoride adsorption was decreased in the presence of phosphate followed by carbonate and sulphate. Results from this study demonstrated potential utility of GFH that could be developed into a viable technology for fluoride removal from drinking water. 相似文献
997.
Rodríguez-Agudelo Y Riojas-Rodríguez H Ríos C Rosas I Sabido Pedraza E Miranda J Siebe C Texcalac JL Santos-Burgoa C 《The Science of the total environment》2006,368(2-3):542-556
Overexposure to manganese (Mn) causes neurotoxicity (a Parkinson-like syndrome) or psychiatric damage ("manganese madness"). Several studies have shown alterations to motor and neural behavior associated with exposure to Mn in the workplace. However, there are few studies on the effects of environmental exposure of whole populations. We studied the risk of motor alterations in people living in a mining district in Mexico. We studied 288 individual people (168 women and 120 men) from eight communities at various distances from manganese extraction or processing facilities in the district of Molango. We measured manganese concentrations in airborne particles, water, soil and crops and evaluated the possible routes of Mn exposure. We also took samples of people's blood and determined their concentrations of Mn and lead (Pb). We used "Esquema de Diagnóstico Neuropsicológico" Ardila and Ostrosky-Solís's neuropsychological battery to evaluate motor functions. Concentrations of Mn in drinking water and maize grain were less than detection limits at most sampling sites. Manganese extractable by DTPA in soils ranged between 6 and 280 mg kg(-1) and means were largest close to Mn extraction or processing facilities. Air Mn concentration ranged between 0.003 and 5.86 microg/m(3); the mean value was 0.42 microg/m(3) and median was 0.10 microg/m(3), the average value (geometric mean) resulted to be 0.13 microg/m(3). Mean blood manganese concentration was 10.16 microg/l, and geometric mean 9.44 microg/l, ranged between 5.0 and 31.0 mcrog/l. We found no association between concentrations of Mn in blood and motor tests. There was a statistically significant association between Mn concentrations in air and motor tests that assessed the coordination of two movements (OR 3.69; 95% CI 0.9, 15.13) and position changes in hand movements (OR 3.09; CI 95% 1.07, 8.92). An association with tests evaluating conflictive reactions (task that explores verbal regulations of movements) was also found (OR 2.30; CI 95% 1.00, 5.28). It seems from our results that people living close to the manganese mines and processing plants suffer from an incipient motor deficit, as a result of their inhaling manganese-rich dust. 相似文献
998.
Novak M Brizova E Adamova M Erbanova L Bottrell SH 《The Science of the total environment》2008,390(2-3):425-436
Under predicted scenarios of global climate change, peatlands may become a net source of greenhouse gases which will accelerate warming of the atmosphere. Comparative studies of peat bogs along present climatic gradients may provide an insight into the future response of boreal and subarctic peatlands to changing temperature and moisture. Three maritime peat bogs in the British Isles, and two high-elevation peatlands in the Czech Republic were studied. All sites were relatively wet, the mean annual temperatures were higher by up to 6 degrees C at the British/Irish sites than at the Czech sites. Cumulative carbon content in (210)Pb-dated Sphagnum-dominated vertical peat cores increased from the warmer to the colder sites when evaluated for the most recent decades (since ca. 1950). That would correspond to formation of thinner, more highly decomposed peat deposits over the long-term in warmer conditions, and deeper peat bogs in colder conditions. However, when cumulative carbon content was evaluated for the last ca. 150 years, no relationship was found between mean annual temperature and the carbon pool size. Even along broad present-day climatic gradients, site-specific factors controlled organic carbon preservation in peat. Pollen analysis was instrumental in corroborating the (210)Pb dates, identifying wet and dry periods in the past, and it also provided evidence for increasing nitrogen loads in wetland areas. 相似文献
999.
Abstract Visual surrogates have been widely used for solving environment related issues. Researchers now have concern over the validity of surrogates. Human perception is multi-modal (Wohlwill, 1976; Ittelson, 1973) and motion is an essential aspect in the perceptual process (Gibson, 1979). Therefore, a surrogate has to be able to represent the dynamic elements in the environment and more realistically reflect human environmental experience. The purpose of this study was to examine the validity of videos and slides as visual surrogates for representing dynamic environment. The validity of the surrogates was verified by comparing subjects' perceptual responses to on-site and simulated situations. The perceptual assessments included emotional, cognitive, behavioural and preference responses. The results indicated that on-site participants' emotional responses and preferences are significantly stronger than those of video and slide viewers. In addition, on-site participants' and video viewers' cognitive and behavioural responses were significantly higher than those of slide viewers. Overall, the validity of videos and slides for representing waterscapes was not supported. 相似文献
1000.
The aim of this paper is to explore how a theoretical framework of ‘architecture’ might be configured, one which would serve as a cross-cultural tool to understanding the nature of constructed and composed environments used as human habitats across all cultural contexts. Drawing on the overall framework of theoretical ideas assembled in the paper, we derive a working definition of architecture as one that is a selected, arranged and constructed configuration of environmental properties, both natural and artificial, in and around one or more activity spaces or behavioral settings, combined with patterns of behavioral rules and meanings, as well as incorporating cultural constructs of space and time to result in human comfort and quality of lifestyle. Examples are drawn from Australian, Central American and Pacific Indigenous cultures throughout this analysis.1 相似文献