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In this paper, we utilize density functional theory to explore how alloying the carbide and nitride of a group IVB transition metal affects the phase stability and mechanical properties; we place an emphasis on elastic and dislocation properties, taking the HfC-HfN system as an example. An evolutionary algorithm is used to identify the ordered carbonitrides and the enthalpies of formation are compared with special quasi-random structures to identify this system's tendency to order and form a solid solution. The variation of elastic constants with composition is examined, and the computed elastic constants are used to predict the theoretical hardness. The GSF curves for various compositions are computed to determine how alloying would affect dislocation behavior. These results show that while there may be a modest peak in elastic response, the resistance to dislocation motion does not particularly show a peak. Furthermore, the alloying of HfC with HfN reduces the resistance to slip almost universally, and helps stabilize dislocations on {111} planes through the stabilization of an intrinsic stacking fault. These results are compared to previous in-depth analysis of the HfC-TaC system, allowing for comparisons between metal and non-metal alloying strategies.

The error negativity/error-related negativity (Ne/ERN) is one of the most well-studied event-related potential (ERP) components in the electroencephalography (EEG) literature. Peaking about 50 ms after the commission of an error, the Ne/ERN is a negative deflection in the ERP waveform that is thought to reflect error processing in the brain. While its relationships to trait constructs such as anxiety are well-documented, there is still little known about how the Ne/ERN may subsequently influence task-related behavior. In other words, does the occurrence of the Ne/ERN trigger any sort of error corrective process, or any other behavioral adaptation to avoid errors? Several theories have emerged to explain how the Ne/ERN may implement or affect behavior on a task, but evidence supporting each has been mixed. In the following manuscript, we review these theories, and then systematically discuss the reasons that there may be discrepancies in the literature. We review both the inherent biological factors of the neural regions that underlie error-processing in the brain, and some of the researcher-induced factors in analytic and experimental choices that may be exacerbating these discrepancies. We end with a table of recommendations for future researchers who aim to understand the relationship between the Ne/ERN and behavior.

Abstract The Targeting Induced Local Lesions in Genomes (TILLING) technology is a reverse genetic strategy broadly applicable to every kind of genome and represents an attractive tool for functional genomic and agronomic applications. It consists of chemical random mutagenesis followed by high-throughput screening of point mutations in targeted genomic regions. Although multiple methods for mutation discovery in amplicons have been described, next-generation sequencing (NGS) is the tool of choice for mutation detection because it quickly allows for the analysis of a large number of amplicons. The aim of the present work was to screen a previously generated sunflower TILLING population and identify alterations in genes involved in several important and complex physiological processes. Twenty-one candidate sunflower genes were chosen as targets for the screening. The TILLING by sequencing strategy allowed us to identify multiple mutations in selected genes and we subsequently validated 16 mutations in 11 different genes through Sanger sequencing. In addition to addressing challenges posed by outcrossing, our detection and validation of mutations in multiple regulatory loci highlights the importance of this sunflower population as a genetic resource.

Abstract Little has been seismically imaged through the lithosphere and mantle at rifted margins across the continent‐ocean transition. A 2014–2015 community seismic experiment deployed broadband seismic instruments across the shoreline of the eastern North American rifted margin. Previous shear‐wave splitting along the margin shows several perplexing patterns of anisotropy, and by proxy, mantle flow. Neither margin parallel offshore fast azimuths nor null splitting on the continental coast obviously accord with absolute plate motion, paleo‐spreading, or rift‐induced anisotropy. Splitting measurements, however, offer no depth constraints on anisotropy. Additionally, mantle structure has not yet been imaged in detail across the continent‐ocean transition. We used teleseismic S, SKS, SKKS, and PKS splitting and differential travel times recorded on ocean‐bottom seismometers, regional seismic networks, and EarthScope Transportable Array stations to conduct joint isotropic/anisotropic tomography across the margin. The velocity model reveals a transition from fast, thick, continental keel to low velocity, thinned lithosphere eastward. Imaged short wavelength velocity anomalies can be largely explained by edge‐driven convection or shear‐driven upwelling. We also find that layered anisotropy is prevalent across the margin. The anisotropic fast polarization is parallel to the margin within the asthenosphere. This suggests margin parallel flow beneath the plate. The lower oceanic lithosphere preserves paleo‐spreading‐parallel anisotropy, while the continental lithosphere has complex anisotropy reflecting several Wilson cycles. These results demonstrate the complex and active nature of a margin which is traditionally considered tectonically inactive.

As driving functions become increasingly automated, motorists run the risk of becoming cognitively removed from the driving process. Psychophysiological measures may provide added value not captured through behavioral or self-report measures alone. This paper provides a selective review of the psychophysiological measures that can be utilized to assess cognitive states in real-world driving environments. First, the importance of psychophysiological measures within the context of traffic safety is discussed. Next, the most commonly used physiology-based indices of cognitive states are considered as potential candidates relevant for driving research. These include: electroencephalography and event-related potentials, optical imaging, heart rate and heart rate variability, blood pressure, skin conductance, electromyography, thermal imaging, and pupillometry. For each of these measures, an overview is provided, followed by a discussion of the methods for measuring it in a driving context. Drawing from recent empirical driving and psychophysiology research, the relative strengths and limitations of each measure are discussed to highlight each measures' unique value. Challenges and recommendations for valid and reliable quantification from lab to (less predictable) real-world driving settings are considered. Finally, we discuss measures that may be better candidates for a near real-time assessment of motorists' cognitive states that can be utilized in applied settings outside the lab. This review synthesizes the literature on in-vehicle psychophysiological measures to advance the development of effective human-machine driving interfaces and driver support systems.

Understanding and quantifying listening effort (LE) is important to a better understanding of speech perception in acoustically challenging environments. EEG alpha power has shown promise as a measure of LE, but relationships between acoustic challenge and alpha have been inconsistent in prior work. We test whether these mixed findings are attributed to differences in alpha power measurement across studies. We compared traditional bandwidth measurement of alpha power to an algorithmic spectral parameterization (SP) approach which separates alpha from background changes in broadband aperiodic activity. Whereas the traditional approach yielded no significant difference in alpha between speech in quiet versus in background noise, the SP approach, which accounts for flattening of the broadband slope in noise, yielded a significant increase in alpha power to speech in noise. These results highlight the importance of accounting for aperiodic brain activity when considering oscillatory EEG markers of cognitive demand in speech perception.

Effective language understanding is crucial to maintaining cognitive abilities and learning new information through adulthood. However, age-related declines in working memory (WM) have a robust negative influence on multiple aspects of language comprehension and use, potentially limiting communicative competence. In the current study (N = 41), we examined the effects of a novel home-based computerized cognitive training program targeting verbal WM on changes in verbal WM and language comprehension in healthy older adults relative to an active component-control group. Participants in the WM training group showed non-linear improvements in performance on trained verbal WM tasks. Relative to the active control group, WM training participants also showed improvements on untrained verbal WM tasks and selective improvements across untrained dimensions of language, including sentence memory, verbal fluency, and comprehension of syntactically ambiguous sentences. Though the current study is preliminary in nature, it does provide initial promising evidence that WM training may influence components of language comprehension in adulthood and suggests that home-based training of WM may be a viable option for probing the scope and limits of cognitive plasticity in older adults.

Abstract: Little has been seismically imaged through the lithosphere and mantle at rifted margins across the continent‐ocean transition. A 2014–2015 community seismic experiment deployed broadband seismic instruments across the shoreline of the eastern North American rifted margin. Previous shear‐wave splitting along the margin shows several perplexing patterns of anisotropy, and by proxy, mantle flow. Neither margin parallel offshore fast azimuths nor null splitting on the continental coast obviously accord with absolute plate motion, paleo‐spreading, or rift‐induced anisotropy. Splitting measurements, however, offer no depth constraints on anisotropy. Additionally, mantle structure has not yet been imaged in detail across the continent‐ocean transition. We used teleseismic S, SKS, SKKS, and PKS splitting and differential travel times recorded on ocean‐bottom seismometers, regional seismic networks, and EarthScope Transportable Array stations to conduct joint isotropic/anisotropic tomography across the margin. The velocity model reveals a transition from fast, thick, continental keel to low velocity, thinned lithosphere eastward. Imaged short wavelength velocity anomalies can be largely explained by edge‐driven convection or shear‐driven upwelling. We also find that layered anisotropy is prevalent across the margin. The anisotropic fast polarization is parallel to the margin within the asthenosphere. This suggests margin parallel flow beneath the plate. The lower oceanic lithosphere preserves paleo‐spreading‐parallel anisotropy, while the continental lithosphere has complex anisotropy reflecting several Wilson cycles. These results demonstrate the complex and active nature of a margin which is traditionally considered tectonically inactive.

Purpose: Previous studies have suggested that the negative effects of acoustic challenge on speech memory can be attenuated with assistive text captions, particularly among older adults with hearing impairment. However, no studies have systematically examined the effects of text-captioning errors, which are common in automated speech recognition (ASR) systems. Method: In two experiments, we examined memory for text-captioned speech (with and without background noise) when captions had no errors (control) or had one of three common ASR errors: substitution, deletion, or insertion errors. Results: In both Experiment 1 (young adults with normal hearing) and Experiment 2 (older adults with varying hearing acuity), we observed similar additive effects of caption errors and background noise, such that increased background noise and the presence of captioning errors negatively impacted memory outcomes. Notably, the negative effects of captioning errors were largest among older adults with increased hearing thresholds, suggesting that older adults with hearing loss may show an increased reliance on text captions compared to adults with normal hearing. Conclusion: Our findings show that even a single-word error can be deleterious to memory for text-captioned speech, especially in older adults with hearing loss. Therefore, to produce the greatest benefit to memory, it is crucial that text captions are accurate.

The Targeting Induced Local Lesions in Genomes (TILLING) technology is a reverse genetic strategy broadly applicable to every kind of genome and represents an attractive tool for functional genomic and agronomic applications. It consists of chemical random mutagenesis followed by high-throughput screening of point mutations in targeted genomic regions. Although multiple methods for mutation discovery in amplicons have been described, next-generation sequencing (NGS) is the tool of choice for mutation detection because it quickly allows for the analysis of a large number of amplicons. The aim of the present work was to screen a previously generated sunflower TILLING population and identify alterations in genes involved in several important and complex physiological processes. Twenty-one candidate sunflower genes were chosen as targets for the screening. The TILLING by sequencing strategy allowed us to identify multiple mutations in selected genes and we subsequently validated 16 mutations in 11 different genes through Sanger sequencing. In addition to addressing challenges posed by outcrossing, our detection and validation of mutations in multiple regulatory loci highlights the importance of this sunflower population as a genetic resource.

We investigated how struggling adult readers make use of sentence context to facilitate word processing when comprehending spoken language, conditions under which print decoding is not a barrier to comprehension. Stimuli were strongly and weakly constraining sentences (as measured by cloze probability), which ended with the most expected word based on those constraints or an unexpected but plausible word. Community-dwelling adults with varying literacy skills listened to continuous speech while their EEG was recorded. Participants, regardless of literacy level, showed N400 effects yoked to the cloze probability of the targets, with larger N400 amplitudes for less expected than more expected words. However, literacy-related differences emerged in an earlier time window of 170-300 ms: higher literacy adults produced a reduced negativity for strongly predictable targets over anterior channels, similar to previously reported effects on the Phonological Mapping Negativity (PMN), whereas low-literacy adults did not. Collectively, these findings suggest that in auditory sentence processing literacy may not notably affect the incremental activation of semantic features, but that comprehenders with underdeveloped literacy skills may be less likely to engage predictive processing. Thus, basic mechanisms of comprehension may be recruited differently as a function of literacy development--even in spoken language.

We employed self-paced reading and event-related potential measures to investigate how adults of varying literacy levels use sentence context information when reading. Community-dwelling participants read strongly and weakly constraining sentences that ended with expected or unex- pected target words. Skilled readers showed N400s that were graded by the cloze probability of the targets, with larger N400s for more unexpected words. Moreover, it took these participants longer to read unexpected targets in strongly than weakly constraining sentences, suggesting a pro- cessing cost for revising predictions. Among less skilled readers, a reliable N400 difference was found between expected and unexpected targets only for the strongly constraining sentences. They also took longer when targets were unexpected, regardless of the context. These findings suggest that lower literacy readers could only immediately take advantage of strongly constraining context information to facilitate word processing and that they do not make as much use of predictive processing during comprehension. [This article was published in "Scientific Studies of Reading" (EJ1152116).]

Little is known about conceptual integration processes and their contributions to memory representations that are constructed in sentence comprehension among adults with underdeveloped literacy skills. We measured word-by-word reading time to examine variation of responsiveness to demands of lexical and conceptual processing during sentence comprehension in a sample of adults with reading proficiency ranging from 4th grade through college-level. Relative to those of their more skilled counterparts, the reading times of adults with lower levels of literacy skill were more sensitive to word-level features, but showed a reduced lengthening at sentence-final words ("wrap up"), which has been argued to reflect conceptual integration processing. They also showed poorer sentence memory. However, regardless of literacy level, readers with better overall sentence memory engaged in a reading strategy marked by a larger sentence wrap-up effect. These findings suggest a pathway to intervention for struggling adult readers.

Although the impact of acoustic challenge on speech processing and memory increases as a person ages, older adults may engage in strategies that help them compensate for these demands. In the current preregistered study, older adults (n = 48) listened to sentences—presented in quiet or in noise—that were high constraint with either expected or unexpected endings or were low constraint with unexpected endings. Pupillometry and EEG were simultaneously recorded, and subsequent sentence recognition and word recall were measured. Like young adults in prior work, we found that noise led to increases in pupil size, delayed and reduced ERP responses, and decreased recall for unexpected words. However, in contrast to prior work in young adults where a larger pupillary response predicted a recovery of the N400 at the cost of poorer memory performance in noise, older adults did not show an associated recovery of the N400 despite decreased memory performance. Instead, we found that in quiet, increases in pupil size were associated with delays in N400 onset latencies and increased recognition memory performance. In conclusion, we found that transient variation in pupil-linked arousal predicted trade-offs between real-time lexical processing and memory that emerged at lower levels of task demand in aging. Moreover, with increased acoustic challenge, older adults still exhibited costs associated with transient increases in arousal without the corresponding benefits. [ABSTRACT FROM AUTHOR]

Historically, Irish Travellers have experienced social exclusion and marked educational disadvantage. Less than 1% of Travellers are documented as being in third-level education, with only 167 adult Travellers reported as holding a third-level qualification (0.5%). This low rate of participation has been targeted by the Department of Further and Higher Education, Research, Innovation and Science (DFHERIS) Programme for Access to Higher Education (PATH). The PATH programme (Strand 3) funded partnership initiatives between higher education institutes in regional clusters. The SOAR partnership initiative in the South Cluster developed a Travellers in Education workstream which delivered three key initiatives: (1) two Leadership in the Community courses delivered at University College Cork (UCC); (2) a Mentoring in Education course delivered at Munster Technological University (MTU) Kerry Campus and (3) a Traveller Graduate Network (TGN) developed at Munster Technological University (MTU) Cork Campus. Two of these initiatives (1 and 2) are bespoke part-time courses for adult learners and the third is a network to support Travellers accessing full-time higher education. Drawing from evaluations of these three initiatives, this paper provides insights into Travellers’ experience of accessing and progressing through Higher Education and identifies supports and barriers. [ABSTRACT FROM AUTHOR]

Language comprehension can be facilitated by the accurate prediction of upcoming words, but prediction effects are not ubiquitous, and comprehenders likely use predictive processing to varying degrees depending on task demands. To ascertain the processing consequences of prioritizing prediction, we here compared ERPs elicited when young adult participants simply read for comprehension with those collected in a subsequent block that required active prediction. We were particularly interested in frontally‐distributed post‐N400 effects for expected and unexpected words in strongly constraining contexts, which have previously been documented as two distinct patterns: an enhanced positivity ("anterior positivity") observed for prediction violations compared to words that are merely unpredictable (because they occur in weakly constraining sentences) and a distinction between expected endings in more constraining contexts and those same weakly constrained words ("frontal negativity" to the strongly predicted words). We found that the size of the anterior positivity effect was unchanged between passive comprehension and active prediction, suggesting that some processes related to prediction may engage state‐like networks. On the other hand, the frontal negativity showed graded patterns from the interaction of task and sentence type. These differing patterns support the hypothesis that there are two separate effects with frontal scalp distributions that occur after the N400 and further suggest that the impact of violating predictions (as long as prediction is engaged at all) is largely stable across varying levels of effort/attention directed toward prediction, whereas other comprehension processes can be modulated by task demands. A comparison of event‐related potentials across a passive comprehension task and an active prediction task examined the consequences of prioritizing prediction and the underlying mechanisms. N400 expectancy effects and a late frontal negativity were enhanced by active prediction, but the late anterior positivity, a marker of prediction consequences, was unchanged, suggesting that some comprehension processes are sensitive to task demands while others are more state‐like. [ABSTRACT FROM AUTHOR]

Both anxiety and working memory capacity appear to predict increased (more negative) error‐related negativity (ERN) amplitudes, despite being inversely related to one another. Until the interactive effects of these variables on the ERN are clarified, there may be challenges posed to our ability to use the ERN as an endophenotype for anxiety, as some have suggested. The compensatory error monitoring hypothesis suggests that high trait‐anxiety individuals have larger ERN amplitudes because they must employ extra, compensatory efforts to override the working memory demands of their anxiety. Yet, to our knowledge, no ERN study has employed direct manipulation of working memory demands in conjunction with direct manipulations of induced (state) anxiety. Furthermore, little is known about how these manipulations affect other measures of error processing, such as the error‐related pupil dilation response and post‐error behavioral adjustments. Therefore, we manipulate working memory load and anxiety in a 2 × 2 within‐subjects design to examine the interactive effects of working memory load and anxiety on ERN amplitude, error‐related pupil dilation response amplitude, and post‐error behavior. There were no effects of our manipulations on ERN amplitude, suggesting a strong interpretation of compensatory error‐processing theory. However, our worry manipulation affected post‐error behavior, such that worry caused a reduction in post‐error accuracy. Additionally, our working memory manipulation affected error‐related PDR magnitude and the amplitude of the error‐related positivity (Pe), such that increased working memory load decreased the amplitude of these responses. Implications of these results within the context of the compensatory error processing framework are discussed. Working memory load and anxiety appear to influence error‐processing, particularly the error‐related negativity (ERN). However, their interactive effects on error‐processing are still not well understood, particularly in the context of state manipulations. The present study is the first, to our knowledge, to simultaneously manipulate both working memory load and anxiety induction in an ERN paradigm. We also make a novel contribution to the literature by recording simultaneous pupillometry in the same paradigm. [ABSTRACT FROM AUTHOR]

The use of prediction can aid language comprehension through preactivation of relevant word features. However, predictions can be wrong, and it has been proposed that resolving the mismatch between the predicted and presented item requires cognitive resources. Older adults tend not to predict and instead rely more on passive comprehension. Here, we tested, using an intraindividual approach, whether older adults consistently use this less demanding processing strategy while reading or whether they attempt to predict on some trials. We used a cross-task conflict paradigm. Younger and older participants self-paced to read sentences that ended with either an expected or unexpected word. Each sentence was then followed by a flanker stimulus that could be congruent or incongruent. We examined responses within and across the two tasks. Unexpected words were in general read as quickly as expected words, indicating that typical processing of these words was similar. However, for both younger and older adults, there was a greater proportion of very slow trials for unexpected words, revealing different processing on a subset of trials. Critically, in older adults, these slowly read unexpected words engaged control, as seen in speeded responses to incongruent flanker stimuli. Using a cross-task conflict paradigm, we showed that older adults are able to predict and engage cognitive resources to cope with prediction violations, but do not opt to use these processes consistently. [ABSTRACT FROM AUTHOR]