Direct Assessments of the Processing Time Hypothesis for the Missing-Letter Effect.

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequently used words or in the most frequent meaning of a polysemic word. According to the processing time hypothesis, this occurs because familiar words and meanings are identified faster, leaving less time for letter identification. Contrary to the predictions of the processing time hypothesis, with a rapid serial visual presentation procedure, participants were slower at detecting target letters for more frequent words or the most frequent meaning of a word (Experiments 1 and 2) or at detecting the word itself instead of a target letter (Experiment 3). In Experiments 4 and 5, participants self-initiated the presentation of each word, and the same pattern of results was observed as in Experiments 1 and 3. Positive correlations were also found between omission rate and response latencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Work function tuning for flexible transparent electrodes based on functionalized metallic single walled carbon nanotubes

We present a method to control the work function of metallic carbon nanotube transparent electrodes by functionalization of the random network with metallic nanoparticles. Flexible functionalized electrodes with high transparency (～90%) can be obtained with work function values ranging from ～4.6 up to ～5.1 eV, depending on the nature of the nanoparticles. The work function values were obtained by comparative in situ Kelvin probe force microscopy under ultra high vacuum and ultraviolet photoelectron spectroscopy measurements. Interestingly, by appropriate choice of the metal source for functionalization, work function engineering can lead to work function values higher or lower than that for pristine metallic nanotubes. This could be of great interest for adjusting the work function of transparent electrodes to active layers in many optoelectronics devices.     

The role of eye movements in the missing-letter effect revisited with the rapid serial visual presentation procedure.

When participants read a text while searching for a target letter, they are more likely to miss the target letter embedded in frequent function words than in less frequent content words. This effect is usually observed with a text displayed normally, for which it has been found that frequent function words are fixated for a smaller amount of time than less frequent content words. However, similar pattern of omissions have been observed with a rapid serial visual presentation procedure in which words appear one at a time. These parallel results would demonstrate that fixation duration per se is not the proximal cause of the missing-letter effect only if eye movements are not made during the rapid serial visual presentation procedure. Therefore, the authors performed eye monitoring during the rapid serial visual presentation procedure. Results revealed that, with a rapid serial visual presentation procedure, participants fixated function and content words for almost the entire presentation duration. It is concluded that eye movements are not the proximal cause of the missing-letter effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of parafoveal processing on the missing-letter effect.

According to the parafoveal-processing hypothesis, letters are more often missed in function words than in content words because the former are more likely to be identified in the parafovea, where letter processing is not available. Contrary to previous demonstrations, more omissions occurred in function words than in content words when parafoveal processing was not available because words were displayed in column format, text was read through a 5-letter window, or words were presented 1 at a time on a computer screen. In all experiments, impeding parafoveal processing decreased omission rates for function but not for content words. In the last experiment, direct monitoring of eye movements revealed that, for both fixated and skipped words, letters in function words are missed more often than content words. These results are best interpreted within a model including the structural precedence hypothesis and stressing the importance of visual factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Combinatorial Multicomponent Access to Natural‐Products‐Inspired Peptidomimetics: Discovery of Selective Inhibitors of Microbial Metallo‐aminopeptidases

The development of selective inhibitors of microbial metallo‐aminopeptidases is an important goal in the pursuit of antimicrobials for therapeutic applications. Herein, we disclose a combinatorial approach relying on two Ugi reactions for the generation of peptidomimetics inspired by natural metallo‐aminopeptidase inhibitors. The library was screened for inhibitory activity against the neutral metallo‐aminopeptidase of Escherichia coli (ePepN) and the porcine kidney cortex metallo‐aminopeptidase (pAPN), which was used as a model of the M1‐aminopeptidases of mammals. Six compounds showed typical dose–response inhibition profiles toward recombinant ePepN, with two of them being very potent and highly selective for ePepN over pAPN. Another compound showed moderate ePepN inhibition but total selectivity for this bacterial enzyme over its mammalian orthologue at concentrations of physiological relevance. This strategy proved to be useful for the identification of lead compounds for further optimization and development.     

Immediate serial recall, word frequency, item identity and item position.

Investigated the effect of frequency on item recall using phonologically similar vs distinct lists within a standard immediate serial recall paradigm. 18 Ss (mean age 29 yrs) completed an immediate serial recall task, where the lists to be recalled consisted of either high-, medium-, or low-frequency items and were also either phonologically similar or distinct. Results show that increasing frequency enhanced item information recall but had no effect on order recall. Conversely, increasing phonological similarity had a detrimental effect on order recall but no significant effect on item recall. The authors maintain that both results reflect retrieval processes where degraded representations are reconstructed on the basis of long-term knowledge. Low-frequency words have reduced accessibility, lowering the probability of correct reconstruction, and phonologically similar items are more easily confused with other recall candidates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High-Temperature Oxidation and Corrosion of Structural Materials in Molten Chlorides

A molten salt-based process for treatment of spent oxide fuels is under development at the Argonne National Laboratory. A major part of the development effort involves identification of corrosion-resistant structural materials for the process vessels. Coupons of two stainless steels, tantalum, and two Inconel alloys were submitted to a corrosion test in an argon atmosphere with 10% oxygen. The coupons were partially immersed in molten lithium chloride salt containing small amounts of lithium metal, lithium oxide, and lithium nitride. Two sets of coupons were tested, the first at 750°C for 30 days and the second at 650°C for 6 days. Coupons of the first set corroded completely. In the second set of coupons, all corroded to some extent, but Inconel 600 showed the best performance overall. The salt-exposed region generally showed the greatest corrosion in the other coupons. One of the 316L SS coupons was welded and the weld area was severely attacked.     

Further evidence that similar principles govern recall from episodic and semantic memory: The Canadian prime ministerial serial position function.

The serial position function, with its characteristic primacy and recency effects, is one of the most ubiquitous findings in episodic memory tasks. In contrast, there are only two demonstrations of such functions in tasks thought to tap semantic memory. Here, we provide a third demonstration, showing that free recall of the prime ministers of Canada also results in a serial position function. Scale Independent Memory, Perception, and Learning (SIMPLE), a local distinctiveness model of memory that was designed to account for serial position effects in episodic memory, fit the data. According to SIMPLE, serial position functions observed in episodic and semantic memory all reflect the relative distinctiveness principle: items will be well remembered to the extent that they are more distinct than competing items at the time of retrieval. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran releases into the atmosphere from the use of secondary fuels in cement kilns during clinker formation

The aim of this study was to evaluate the influence of using waste materials, such as tires or meat meal, as a secondary fuel during clinker production on the polychlorinated dibenzo-p-dioxin (PCDD)/polychlorinated dibenzofuran (PCDF) emission levels to the atmosphere. For this purpose, three different cement plants in Spain were chosen to conduct the project in different sampling episodes. Different materials were separately evaluated in each plant: the first plant included the addition of meat meal in the kiln, the second plant used rejected tires, and the third plant used a mixture of both. In all cases, PCDD/F emission values remained below the limit established by the European Union Directive of 0.1 ng I-TEQ/Nm3, with values ranging from 0.001 to 0.042 ng I-TEQ/Nm3. The major contribution to total TEQ in the majority of cases came from 2,3,7,8-tetrachlorodibenzofuran owing to its relatively higher levels and 2,3,4,7,8-pentachlorodibenzofuran because of its TEF of 0.5. The remaining 15 toxic congeners collectively provided only a minor contribution to TEQ. Furthermore, no marked differences were found compared with reported data obtained from Spanish cement kiln plants using conventional fuel. This fact indicates that the addition of used tires or meat meals had no effect on PCDD/PCDF emission levels.     

One Missing-Letter Effect: Two Methods of Assessment.

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequent function words than in less frequent content words. This effect is usually observed with a paper and pencil procedure. It has been shown that a similar pattern is observed using a rapid serial visual presentation procedure in which words appear one at a time on a computer screen. It has been questioned, however, whether the two methods tap the same cognitive processes. Item-based correlations between the paper and pencil and the rapid serial visual presentation procedure were high and not significantly different from reliability estimates of either procedure. It is concluded that both procedures highlight the same cognitive processes that are responsible for the missing- letter effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)