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181.
182.
Selection of promising lactic acid bacteria as starter cultures for sourdough: using a step‐by‐step approach through quantitative analyses and statistics 下载免费PDF全文
183.
The IBM ADF-II is a promising and powerful tool for online application development Using ADF-II, programmers code logical transactions, not programs—this results in long-term benefits that include the smooth transition to DBMS capabilities and new types of computers that will upgrade the entire set of applications. 相似文献
184.
Daniela de Oliveira Ribeiro Bianca Waruar Lobo Nádia Maria Volpato Venício Féo da Veiga Mendes Lúcio Cabral Valeria Pereira de Sousa 《Nutrition journal》2009,8(1):51-13
Background
Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use. 相似文献185.
186.
Daniela Aiello Flaviano Testa Rosario Aiello Luca Malfatti Tongjit Kidchob Plinio Innocenzi Iolinda Aiello Tonino Martino Mauro Ghedini Massimo La Deda 《Inorganic chemistry communications》2009,12(3):237-239
A luminescent zinc complex was successfully incorporated to mesostructured porous titania films through a grafting process. The resulting films show an intense blue-emission increasing with functionalization time. The emission quantum yield of these newly synthesized films was quantitatively and accurately determined by measurements carried by an integrating sphere. 相似文献
187.
When individuals reach very old age, accumulating negative conditions represent a serious challenge to their capacity to adapt and are likely to reduce the quality of life. By examining happiness and its determinants in centenarians, this study investigated the proposal that psychological resilience may come to an end in extremely old age. Data from the population-based Heidelberg Centenarian Study indicated high levels of happiness. Basic resources (i.e., job training, cognition, health, social network, extraversion) explained a substantial proportion of variance in happiness, but some resource effects were mediated through self-referent beliefs (e.g., self-efficacy) and attitudes toward life (e.g., optimistic outlook). Results challenge the view that psychological resilience reaches a critical limit or that the self-regulatory adaptation system loses its efficiency in very advanced age. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
188.
Computational Markets to Regulate Mobile-Agent Systems 总被引:9,自引:0,他引:9
Bredin Jonathan Kotz David Rus Daniela Maheswaran Rajiv T. Imer Cagri Basar Tamer 《Autonomous Agents and Multi-Agent Systems》2003,6(3):235-263
Mobile-agent systems allow applications to distribute their resource consumption across the network. By prioritizing applications and publishing the cost of actions, it is possible for applications to achieve faster performance than in an environment where resources are evenly shared. We enforce the costs of actions through markets, where user applications bid for computation from host machines.We represent applications as collections of mobile agents and introduce a distributed mechanism for allocating general computational priority to mobile agents. We derive a bidding strategy for an agent that plans expenditures given a budget, and a series of tasks to complete. We also show that a unique Nash equilibrium exists between the agents under our allocation policy. We present simulation results to show that the use of our resource-allocation mechanism and expenditure-planning algorithm results in shorter mean job completion times compared to traditional mobile-agent resource allocation. We also observe that our resource-allocation policy adapts favorably to allocate overloaded resources to higher priority agents, and that agents are able to effectively plan expenditures, even when faced with network delay and job-size estimation error. 相似文献
189.
Daniela BianchiniKátia Messias Bichinho João Henrique Zimnoch dos Santos 《Polymer》2002,43(10):2937-2943
The effect of Al content on MAO-modified silicas was evaluated on catalyst activity, on polymer properties and on residual metal content in the resulting polyethylenes. MAO-modified silicas were prepared by impregnating MAO toluene solutions in concentration range between 0.5 and 20.0 wt% Al/SiO2. Commercial MAO-modified silica (Witco) containing 24.4 wt% Al/SiO2 was used for comparative reasons. The resulting modified-silicas were employed as supports for grafting (nBuCp)2ZrCl2. Using external MAO as cocatalyst (Al/Zr=2000) no difference in catalyst activity was observed. Nevertheless, for Al/Zr=500, catalyst activities were shown to be higher for supported zirconocene systems containing 0.0-2.0 wt% Al/SiO2 range. According to DSC analysis, one Tm peak was detected for polymer obtained with catalyst prepared with 0.5 wt% Al/SiO2 (135 °C), but two Tm peaks were observed for polymers obtained with catalysts prepared with 10.0 wt% Al/SiO2 (136 and 141 °C) and 20.0 wt% Al/SiO2 (133 and 141 °C). 相似文献
190.
There has been some controversy in the literature concerning the ability of ±3,4 methylenedioxymethamphetamine (MDMA) to reinforce operant responding in rats. In the present study, operant responding maintained by intravenous MDMA infusions increased when the fixed ratio schedule was increased from 1 to 5, decreased when saline was substituted for MDMA, and increased again when MDMA was reintroduced. During self-administration training, each infusion of MDMA was paired with the illumination of a light stimulus. The role of the continued presentation of this drug-associated stimulus in operant responding was measured in groups of rats that had received comparable exposure (average 19 daily test sessions) to MDMA during training. When either the light stimulus or the drug infusion was omitted, operant responding decreased gradually over the 15-day test period following training. When both the light stimulus and the MDMA infusion were omitted, there was a dramatic decrease in operant responding that persisted for the entire 15-day test period. These findings suggest that cues associated with MDMA develop conditioned properties that might contribute to drug taking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献