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Hearing a task-irrelevant sound during object encoding can improve visual recognition memory when the sound is object-congruent (e.g., a dog and a bark). However, previous studies have only used binary old/new memory tests, which do not distinguish between recognition based on the recollection of details about the studied event or stimulus familiarity. In the present research, we hypothesized that hearing a task-irrelevant but semantically congruent natural sound at encoding would facilitate the formation of richer memory representations, resulting in increased recollection of details of the encoded event. Experiment 1 replicates previous studies showing that participants were more confident about their memory for items that were initially encoded with a congruent sound compared to an incongruent sound. Experiment 2 suggests that congruent object-sound pairings specifically facilitate recollection and not familiarity-based recognition memory, and Experiment 3 demonstrates that this effect was coupled with more accurate memory for audiovisual congruency of the item and sound from encoding rather than another aspect of the episode. These results suggest that even when congruent sounds are task-irrelevant, they promote formation of multisensory memories and subsequent recollection-based retention. Given the ubiquity of encounters with multisensory objects in our everyday lives, considering their impact on episodic memory is integral to building models of memory that apply to naturalistic settings.

Previous studies have tended to infer that reactive control is intact in aging populations because of evidence that proactive control is impaired and that older participants appear to favor reactive control strategies. However, most of these studies did not compare reactive control in young and older participants directly. In our study, a young (18 to 21 years old) and older (60+ years old) cohort engaged in a task that assesses reactive distractor suppression where participants had to discriminate between an upright and inverted T-shape in the presence of a salient or nonsalient distractor. In previous studies using this paradigm (DiQuattro & Geng, 2011) young participants reactively used the salient distractor as an anticue and performed better (faster reaction time [RT] and higher accuracy) when it was present. It was found that older participants were not able to reactively suppress the salient distractor with a 200-ms display but were able to do so with a 600-ms display. It was concluded that the initiation of reactive suppression is delayed for older participants, but that effective suppression is possible given enough time. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Attention operates as a cognitive gate that selects sensory information for entry into memory and awareness (Driver, 2001, British Journal of Psychology, 92, 53–78). Under many circumstances, the selected information is task-relevant and important to remember, but sometimes perceptually salient nontarget objects will capture attention and enter into awareness despite their irrelevance (Adams & Gaspelin, 2020, Attention, Perception, & Psychophysics, 82[4], 1586–1598). Recent studies have shown that repeated exposures with salient distractor will diminish their ability to capture attention, but the relationship between suppression and later cognitive processes such as memory and awareness remains unclear. If learned attentional suppression (indicated by reduced capture costs) occurs at the sensory level and prevents readout to other cognitive processes, one would expect memory and awareness to dimmish commensurate with improved suppression. Here, we test this hypothesis by measuring memory precision and awareness of salient nontargets over repeated exposures as capture costs decreased. Our results show that stronger learned suppression is accompanied by reductions in memory precision and confidence in having seen a color singleton at all, suggesting that such suppression operates at the sensory level to prevent further processing of the distractor object.

The ability to suppress distractions is essential to successful completion of goal-directed behaviors. Several behavioral studies have recently provided strong evidence that learned suppression may be particularly efficient in reducing distractor interference. Expectations about a distractor's repeated location, color, or even presence are rapidly learned and used to attenuate interference. In this study, we use a visual search paradigm in which a color singleton, which is known to capture attention, occurs within blocks with high or low frequency. The behavioral results show reduced singleton interference during the high compared to the low frequency block (Won et al., 2019). The fMRI results provide evidence that the attenuation of distractor interference is supported by changes in singleton, target, and non-salient distractor representations within retinotopic visual cortex. These changes in visual cortex are accompanied by findings that singleton-present trials compared to non-singleton trials produce greater activation in bilateral parietal cortex, indicative of attentional capture, in low frequency, but not high frequency blocks. Together, these results suggest that the readout of saliency signals associated with an expected color singleton from visual cortex is suppressed, resulting in less competition for attentional priority in frontoparietal attentional control regions.

Although schizophrenia is classically thought to involve impaired attentional filtering, people with schizophrenia (PSZ) exhibit a more intense and more exclusive attentional focus than healthy control subjects (HCS) in many tasks. To resolve this contradiction, this functional magnetic resonance imaging study tested the impact of attentional control demands on the modulation of stimulus-induced activation in the fusiform face area and parahippocampal place area when participants (43 PSZ and 43 HCS) were looking for a target face versus house. Stimuli were presented individually, or as face-house overlays that challenged attentional control. Responses were slower for house than face stimuli and when prioritizing houses over faces in overlays, suggesting a difference in salience. Blood-oxygen-level-dependent activity reflected poorer attentional selectivity in PSZ than HCS when attentional control was challenged most, that is, when stimuli were overlaid and the task required detecting the lower-salience house target. By contrast, attentional selectivity was exaggerated in PSZ when control was challenged least, that is, when stimuli were presented sequentially and the task required detecting the higher-salience face target. These findings are consistent with 2 distinct attentional abnormalities in schizophrenia leading to impaired and exaggerated selection under different conditions: attentional control deficits, and hyperfocusing once attention has been directed toward a stimulus.

When searching for an object, we use a target template in memory that contains task-relevant information to guide visual attention to potential targets and to determine the identity of attended objects. These processes in visual search have typically been assumed to rely on a common source of template information. However, our recent work (Yu et al., 2022) argued that attentional guidance and target-match decisions rely on different information during search, with guidance using a “fuzzier” version of the template compared with target decisions. However, that work was based on the special case of search for a target amongst linearly separable distractors (e.g., search for an orange target amongst yellower distractors). Real-world search targets, however, are infrequently linearly separable from distractors, and it remains unclear whether the differences between the precision of template information used for guidance compared with target decisions also applies under more typical conditions. In four experiments, we tested this question by varying distractor similarity during visual search and measuring the likelihood of attentional guidance to distractors and target misidentifications. We found that early attentional guidance is indeed less precise than that of subsequent match decisions under varying exposure durations and distractor set sizes. These results suggest that attentional guidance operates on a coarser code than decisions, perhaps because guidance is constrained by lower acuity in peripheral vision or the need to rapidly explore a wide region of space while decisions about selected objects are more precise to optimize decision accuracy.

Theories of visual attention hypothesize that target selection depends upon matching visual inputs to a memory representation of the target - i.e., the target or attentional template. Most theories assume that the template contains a veridical copy of target features, but recent studies suggest that target representations may shift “off veridical” from actual target features to increase target-to-distractor distinctiveness. However, these studies have been limited to simple visual features (e.g., orientation, color), which leaves open the question if similar principles apply to complex stimuli, such as a face depicting an emotion, the perception of which is known to be shaped by conceptual knowledge (Gendron & Barrett, 2018; Lindquist, Satpute, & Gendron, 2015). In three studies, we find confirmatory evidence for the hypothesis that attention modulates the representation of an emotional face to increase target-to-distractor distinctiveness. This occurs over-and-above strong pre-existing conceptual and perceptual biases in the representation of individual faces. The results are consistent with the view that visual search accuracy is determined by the representational distance between the target template in memory and distractor information in the environment, not the veridical target and distractor features (Geng & Witkowski, 2019).

This paper presents experimental and modelling results of an ultra-compact self-rectifier flux pump energizing a superconducting coil. The device fits inside a volume of 65x65x50~mm and generates up to 320~A dc through the coil and a peak output voltage up to 60~mV. We also develop and present a full electromagnetic effective circuit model of the flux pump and compare its predictions to the experimental results. We show that our model can reproduce accurately the charging of the load coil and that it reproduces the systematic dependence of the maximum load coil current on the input current waveform. The experiments and modelling together show also the importance of dc-flux offsets in the transformer core on the final achievable current through the coil. The miniaturization possible for this class of flux pump and their minimal heat-leak into the cryogenic environment from thermal conduction make them attractive for applications with demanding size, weight and power limitations. Our effective circuit model is a useful tool in the understanding, design and optimization of such flux pumps which will accelerate their progression from research devices to their application., Comment: 9 pages, 8 figures

A Volumetric Method of Moments accelerated by means of iterative solvers combined with FFT matrix-vector products has been presented. The method allows analyzing small lens antennas with their integrated feeds efficiently since different structures and geometries can be studied with the same discretization, just by adding the material characteristics in post-processing.

Models of attention posit that attentional priority is established by summing the saliency and relevancy signals from feature-selective maps. The dimension-weighting account further hypothesizes that information from each feature-selective map is weighted based on expectations of how informative each dimension will be. In the current studies, we investigated the question of whether attentional biases to the features of a conjunction target (color and orientation) differ when one dimension is expected to be more diagnostic of the target. In a series of color-orientation conjunction search tasks, observers saw an exact cue for the upcoming target, while the probability of distractors sharing a target feature in each dimension was manipulated. In one context, distractors were more likely to share the target color, and in another, distractors were more likely to share the target orientation. The results indicated that despite an overall bias toward color, attentional priority to each target feature was flexibly adjusted according to distractor context: RT and accuracy performance was better when the diagnostic feature was expected than unexpected. This occurred both when the distractor context was learned implicitly and explicitly. These results suggest that feature-based enhancement can occur selectively for the dimension expected to be most informative in distinguishing the target from distractors.

Theories of attention hypothesize the existence of an “attentional” or “target” template that contains task-relevant information in memory when searching for an object. The target template contributes to visual search by directing visual attention towards potential targets and serving as a decisional boundary for target identification. However, debate still exists regarding how template information is stored in the human brain. Here, we conducted a pattern-based fMRI study to assess how template information is encoded to optimize target-match decisions during visual search. To ensure that match decisions reflect visual search demands, we used a visual search paradigm in which all distractors were linearly separable but highly similar to the target and were known to shift the target representation away from the distractor features (Yu & Geng, 2019). In a separate match-to-sample probe task, we measured the target representation used for match decisions across two resting state networks that have long been hypothesized to maintain and control target information: the frontoparietal control network (FPCN) and the visual network (VisN). Our results showed that lateral prefrontal cortex in FPCN maintained the context-dependent “off-veridical” template; in contrast, VisN encoded a veridical copy of the target feature during match decisions. By using behavioral drift diffusion modeling, we verified that the decision criterion during visual search and the probe task relied on a common biased target template. Taken together, our results suggest that sensory-veridical information is transformed in lateral prefrontal cortex into an adaptive code of target-relevant information that optimizes decision processes during visual search.

Background Cardiac stromal cells (CSCs) contain a pool of cells with supportive and paracrine functions. Various types of mesenchymal stromal cells (MSCs) can influence CSCs in the cardiac niche through their paracrine activity. Ischemia/reperfusion (I/R) leads to cell death and reduction of the paracrine activity of CSCs. The forced coexpression of telomerase reverse transcriptase (TERT) and myocardin (MYOCD), known to potentiate anti-apoptotic, pro-survival and pro-angiogenic activities of MSCs isolated from the adipose tissue (AT-MSCs), may increase CSC survival, favoring their paracrine activities. Aim To investigate the hypothesis that CSCs feature improved resistance to simulated I/R (SI/R) and increased commitment toward the cardiovascular lineage when preconditioned with conditioned media (CM) or extracellular vesicles (EV) released from AT-MSCs overexpressing TERT and MYOCD (T/M AT-MSCs). Methods and results Murine CSCs were isolated with the cardiosphere (CSps) isolation technique. T/M AT-MSCs and their secretome improved spontaneous intracellular calcium changes and ryanodine receptor expression in aged CSps. The cytoprotective effect of AT-MSCs was tested in CSCs subjected to SI/R. SI/R induced cell death as compared to normoxia (28±4 vs 10±3%, p=0.02). Pretreatment with CM (15±2, p=0.02) or with the EV-enriched fraction (10±1%, p=0.02) obtained from mock-transduced AT-MSCs in normoxia reduced cell death after SI/R. The effect was more prononunced with CM (7±1%, p=0.01) or the EV-enriched fraction (2±1%, p=0.01) obtained from T/M AT-MSCs subjected to SI/R. In parallel, we observed lower expression of the apoptosis marker cleaved caspase-3 and higher expression of cardiac and vascular markers eNOS, sarcomeric α-actinin and cardiac actin. Conclusions The T/M AT-MSCs secretome exerts a cytoprotective effect and promotes development of CSCs undergoing SI/R towards a cardiovascular phenotype. Funding Acknowledgement Type of funding sources: None.

We have searched for weak fast radio burst (FRB) events using a database containing 568,736,756 transient events detected using the Parkes radio telescope between 1997 and 2001. In order to classify these pulses, and to identify likely FRB candidates, we used a machine learning algorithm based on ResNet. We identified 81 new candidate FRBs and provide details of their positions, event times, and dispersion measures. These events were detected in only one beam of the Parkes multibeam receiver. We used a relatively low S/N cutoff threshold when selecting these bursts and some have dispersion measures only slightly exceeding the expected Galactic contribution. We therefore present these candidate FRBs as a guide for follow-up observations in the search for repeating FRBs., 8 pages, 5 figures, 2 tables, accepted by MNRAS

Our sensory environments contain more information than we can process, and successful behaviors require the ability to separate task-relevant information from task-irrelevant information. Much research on attention has focused on the mechanisms that result in selection of desired information, but much less is known about how distracting information is ignored. Here, we describe evidence that strategic, learned, and passive information can all contribute to better distractor ignoring. The evidence suggests that there are multiple ways in which distractor ignoring is supported, and these ways may be different from those of target selection. Future work will need to identify the mechanisms by which each source of information adjusts attentional priority such that irrelevant information is better ignored.

In order to understand the epidemiological status of alveolar and cystic echinococcosis in intermediate and definitive hosts in Qinghai Province, China, during the period 2007-2011, we investigated the infection in humans and animals, including yaks, Tibetan sheep, Tibetan dogs, and wild foxes distributed in different counties around the province. Sera from local residents were examined using a rapid serodiagnostic kit to detect specific antibodies against Echinococcus. Seropositive samples were confirmed with B-scan ultrasonography and X-ray examinations. Yaks and Tibetan sheep were checked at slaughterhouses, and cysts and suspicious lesions were collected for analysis. A rapid diagnostic strip was used to detect Echinococcus adults in Tibetan dogs. Positive dogs were dewormed and the parasites collected. Wild foxes were trapped and necropsies performed with particular attention to the intestine. Forty-eight of 735 (6.4%) humans tested were positive and 475 of 854 (55.6%) Tibetan sheep and 85 of 352 (24.15%) yaks were infected with Echinococcus. Across different counties, 214 of 948 (22.57%) Tibetan dogs were positive, and five of 36 (13.9%) wild foxes were infected with Echinococcus. Molecular studies showed that all the infections detected in humans, domestic yaks, and Tibetan sheep were the G1 genotype (E. granulosus), whereas the parasites from Tibetan foxes and Tibetan dogs were E. shiquicus and E. multilocularis, respectively. In conclusion, Echinococcosis is hyperendemic in Qinghai Province in both its intermediate and definitive hosts and the G1 genotype of cystic Echinococcus is the dominant strain.

Distractions are ubiquitous in our sensory environments. How do we keep them from capturing attention? Existing research has focused primarily on mechanisms of strategic control or statistical learning, both of which require knowledge (explicit or implicit) of what features belong to distractors before suppression occurs. Here, we test the hypothesis that task-free exposure to stimuli is sufficient to attenuate their effect as distractors later on. In 3 experiments, subjects were exposed to either colored or achromatic circles on "circle displays" interleaved with "target search displays." Later, new distractors were introduced into the search displays using colors from the circle displays. We consistently found that passively viewed colors produced less interference when introduced as new visual search distractors. We conclude that learning during passive exposure was due to habituation mechanisms that attenuate sensory responsivity to recurring stimuli, allowing attention to operate more efficiently to select task-relevant targets or novel stimuli. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Background Social well-being of patients with inflammatory bowel disease (IBD) is garnering increased attention; however, the impact of social isolation remains poorly understood. We investigated whether patients with IBD are at a higher risk of social isolation, and whether any such isolation is associated with increased mortality. Methods We investigated 489,731 participants from UK Biobank (including 5,671 with IBD); the mean follow-up was 11.63 years. Diagnoses of IBD and its subtypes of Crohn’s disease (CD) and ulcerative colitis (UC) were confirmed with the combination of self-reporting, primary care, and hospital admission data. Social isolation was measured by the frequency of meeting family/friends, leisure and social activity, and communal/solitary living. Mortality was ascertained through data linkage with national death registries. Logistic regression was used to calculate the association between social isolation and IBD. The association between social isolation and mortality was investigated using multivariable Cox regression models. Results In the fully adjusted model, CD (odd ratio [OR]=1.24, 95% CI: 1.07, 1.42, P=0.003) was cross-sectionally associated with social isolation, whereas UC was not (OR=0.99, 95% CI: 0.89, 1.11, P=0.875). Social isolation was prospectively associated with an elevated risk of incident mortality among patients with CD (HR=2.09, 95% CI: 1.51, 2.89, P Conclusion Patients with CD are more likely to be socially isolated. Socially-isolated patients with CD increases the risk of premature death.

Photogalvanic current and voltage photoinduced by CW laser illumination of Fe-doped LN reveals quasi-periodic pulsing due to microplasmas discharges. This transformation of constant external influence into periodic response is interesting as example of self-excited systems, resembling pulsations of biological systems. Microplasmas discharges are also interesting for applications in various fields, such as surface treatment, sterilization, water splitting. We analyze self-pulsing of photogalvanic current visualized by dynamic electrowetting in a simple LC-cell, formed by a nematic LC droplet placed on Fe-doped LN crystal. In modeling contributions from both photogalvanic (bulk photovoltaic) and pyroelectric (charging by heating-cooling) effect are included. The analysis of dynamic regime reveals that a current pulse (in microsecond range) has asymmetric shape with extremely sharp rise with longer decay time. Reflected interference patterned was modulated by the dynamic electro-wetting effect. For high light intensity power conversion efficiency is enhanced due to nonlinear photogalvanic effect and microplasmas discharges.

Acacia mangium and Leuceana leucocephala are both exotic species known to be planted in Malaysia. Both species are well known to possess high growth rate, therefore made as reforestation species as well as a popular resource for pulp and paper industry. The main objectives of this study are to determine the chemical compositions of small diameter wild Acacia mangium and Leucaena leucocephala species and to compare that properties between of them at three (3) different stem portions (bottom, middle and top) and two (2) different parts (bark and wood). All analyses were done according to TAPPI standard method, except hemicellulose (Wise et al.) and holocellulose (formula). All the data and results were statistically analyzed using ANOVA and Tukey’s Post Hoc test. Results revealed alcohol-toluene solubles was highest in bottom portion of Acacia mangium bark (14.98%). Holocellulose can be found highest in middle portion of Leuceana leucocephala wood (90.61%). For α-cellulose, highest was in Leuceana leucocephala bark (69.36%). Hemicellulose was most abundant in Acacia mangium top portion of wood (36.14%), while highest lignin was in its bottom portion of bark (31.18%). ANOVA indicates there are statistically high significance between species for all chemical composition, but between portions, only alcohol-toluene soluble and holocellulose are significant. For parts, all chemical composition is significant, except for lignin. This study proved that small diameter wild Acacia mangium and Leuceana leucocephala as a viable resource for pulp and paper industry.

In this work, mixed convection heat transfer of nanofluids in a T-shaped lid-driven porous cavity is studied. The governing equations for a simple cavity are studied based on the previous work. It is further changed to complicated porous media and solved by finite element method (FEM). Because shape and dimensions of the T-cavity have significant effects on the heat transfer efficiency and Nusselt number, it is important to find the optimal geometry for this cavity. In our study, a novel response surface methodology (RSM) is applied for the optimization. After finding the optimal geometry of T-shaped cavity, effect of the constant coefficients (such as Reynolds (Re), Richardson (Ri) and Darcy (Da) numbers, etc.) on the Nusselt number, isotherm and streamlines in the cavity are studied and discussed. Furthermore in this study, effect of different nanoparticles (Al2O3, Cu and TiO2) and their volume fraction on Nusselt number is investigated.

Although it is well known that salient nontargets can capture attention despite being task irrelevant, several studies have reported short fixation dwell times, suggesting the presence of an attentional mechanism to "rapidly reject" dissimilar distractors. Rapid rejection has been hypothesized to depend on the strong mismatch between distractor features and the target template, but it is unknown whether the presence of strong feature mismatch is sufficient, or if the presence of a target at a competing location is also necessary. Here, we investigated this question by first replicating the finding of rapid rejection for dissimilar distractors in the presence of a concurrent target (Experiment 1); manipulating the onset of the target stimulus relative to the distractor (Experiment 2); and using a saccade-contingent display to delay the target onset until after the first saccade was initiated. The results demonstrate that the speed of distractor rejection depends on the presence of target competition prior to the initiation of the first saccade, and not after the saccade. This suggests that stimulus competition for covert attention sets a "saccade priority map" that unfolds over time, resulting in faster corrective saccades to an anticipated object with higher top-down attentional priority.