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Attention is the process of selecting relevant information and suppressing irrelevant information. However, it is still controversial whether attentional capture by salient but task‐irrelevant stimuli operates in a bottom‐up fashion (stimulus‐driven theory) or a top‐down fashion (goal‐driven theory) or if even salient distractors can be suppressed before capturing attention (signal suppression theory). In the present study, we investigated how saliency affects attentional capture (indexed by N2‐posterior‐contralateral [N2pc]) and suppression (indexed by distractor positivity [PD]) of abrupt‐onset and color singleton distractors in a visual search task. Experiment 1 showed that an abrupt‐onset distractor elicited both N2pc and PD, while a color singleton distractor elicited only PD. Moreover, the abrupt‐onset distractor elicited a larger N2pc and a larger PD relative to the color singleton distractor. In addition, both distractors elicited an early positive component, the positivity posterior contralateral (Ppc), which was also larger for abrupt onsets than for color singletons. Experiment 2 further demonstrated that when both the abrupt onset and color singleton were designed as targets, and thus required no attentional suppression, Ppc was elicited, but PD was not. This corroborated the finding in Experiment 1 that the later PD, not the early Ppc, reflected attentional suppression. Therefore, a more salient distractor demonstrates stronger early perceptual processing, can capture attention better and needs more attentional resources to be suppressed later. Based on these results, a three‐stage hypothesis is proposed, in which the saliency of a distractor modulates processing at early perception, attentional capture, and suppression stages. We provide strong evidence that attentional capture, measured by the N2pc component, occurs before suppression, measured by the PD component. We proposed a three‐stage model of attentional processing of a salient distractor, in which saliency of the distractor plays a crucial role. Our findings shed light on our understanding of how the visual attention system reacts to salient changes in the environment. [ABSTRACT FROM AUTHOR]

Automatic detection of information changes in the visual environment is crucial for individual survival. Researchers use the oddball paradigm to study the brain's response to frequently presented (standard) stimuli and occasionally presented (deviant) stimuli. The component that can be observed in the difference wave is called visual mismatch negativity (vMMN), which is obtained by subtracting event-related potentials (ERPs) evoked by the deviant from ERPs evoked by the standard. There are three hypotheses to explain the vMMN. The sensory fatigue (or refractoriness) hypothesis considers that weakened neural activity caused by repetition results in decreased ERPs of the standard. The memory trace hypothesis proposes that vMMN results from increased responses to the deviant. The predictive coding hypothesis attributes the difference to enhanced responses for deviants and suppression for standards. However, when distinguishing between these effects, previous researchers did not consider the effect of low-level features on the vMMN. In this experiment, we used face sequences composed of different emotions (e.g., neutral and fearful face) and presented an oddball sequence, a reverse oddball sequence, and an equiprobable sequence to participants. The deviant of the oddball sequence was subtracted from the standard of the oddball sequence, the reverse oddball sequence, and the same type of stimulus of the equiprobable sequence to get oddball-vMMN (vMMN1), reverse oddball-vMMN (vMMN2), and equiprobable-vMMN (vMMN3), respectively. The results showed no significant difference between vMMN2 and vMMN3 in 100–350 ms following stimulus onset, while the vMMN effect was significant, indicating that the probability of the standard did not affect vMMN, which supported the memory trace hypothesis. Additionally, the fearful-related vMMN were more negative than the neutral-related vMMN within the range of 100–150 ms, suggesting a negative bias. We analyzed the source location of different vMMNs. There was no significant difference in brain regions between different vMMNs. Time-frequency analysis showed that the deviant had stronger theta-band oscillatory than the standard (visual mismatch oscillatory responses, vMORs). However, there was no difference between vMORs2 and vMORs3, indicating that vMORs reflect an enhanced response to the deviant in terms of neural oscillation, supporting the memory trace hypothesis. [ABSTRACT FROM AUTHOR]

N170 is a negative event‐related potential (ERP) component in response to visual stimuli, such as faces. It remains controversial whether N170 reflects the specific processing of faces or can also be elicited by objects of expertise (e.g., words). In this research, we conducted a meta‐analysis for the spatiotemporal characteristics of N170 of face and word stimuli from 24 studies in which both stimuli were presented for each subject. We observed that (1) both face and word stimuli can elicit conspicuous N170s and that there was no difference between the amplitude of face‐N170 and word‐N170; (2) there is no difference in the latencies between the two N170s; and (3) both N170s are distributed in the occipitotemporal regions but with a reversed hemispheric distribution pattern—face‐N170 is more negative in the right than left occipitotemporal regions, while word‐N170 is the opposite. These results showed that the face‐ and word‐N170s are qualitatively the same but have different hemispheric lateralization advantages—N170 might be a general neural index of the expertise‐dependent object‐recognition process in occipitotemporal regions. [ABSTRACT FROM AUTHOR]

As one of the reactive oxygen species (ROS), the concentration of hypochlorite (HClO/ClO−) in the environment and in vivo is associated with many diseases and is also quite significant for human health. In this paper, a novel ratiometric fluorescent probe CSN based on thieno[3,2-c]coumarin has been constructed for the detection of hypochlorite. This probe exhibited high selectivity and sensitivity towards HClO/ClO−, and showed a large emission shift (170 nm) and a 338-fold enhancement in the emission ratio (I470/I640). Moreover, investigations for sensing hypochlorite in real water samples and bioimaging in living cells were carried out, and the test results have confirmed the high potential of probe CSN in analytical and bioanalytical applications. [ABSTRACT FROM AUTHOR]

The low electronic conductivity of sulfur and the diffusion and shuttle of polysulfide intermediates are the main obstacles of the cathode that restrain the progress of lithium–sulfur (Li–S) batteries. To address the two main predicaments, we explored a dual functional 3D hierarchical filter element structured Mo2C nanosheet based sulfur electrode. The Mo2C based sulfur electrodes fulfill the requirements of conductivity (30 S cm−1) and entrapment of diffusing polysulfide intermediates, and meanwhile possess the advantages of high crystallinity and large specific surface area. As a filter and reservoir for polysulfides, Mo2C nanosheets possess a strong chemical interaction with polysulfides to mitigate the shuttling of polysulfides. The dual functional Mo2C nanosheet based electrode exhibited a high initial discharge capacity of ca. 1200 mA h g−1 and ca. 800 mA h g−1 after 300 cycles at 0.2C. Moreover, the flexibility of the sulfur electrode is explored through an in situ fabrication on carbon cloth in a soft-package configuration. [ABSTRACT FROM AUTHOR]

The reasonable design of the cathode host material is of great significance for achieving high-efficiency sulfur electrochemistry and increasing the energy density of lithium-sulfur (Li-S) batteries. Herein, a uniformly CeO 2 doped three-dimensional porous nitrogen-rich carbon nanofiber (CeO 2 @CNF) is prepared as an advanced sulfur electrode matrix. Carbon nanofibers with good electrical conductivity and abundant pores can effectively store sulfur and inhibit the shuttle of polysulfides by double physicochemical sulfur coordination. In addition, electrocatalytically active CeO 2 nanocrystals significantly promote stable redox activity. The prepared sulfur electrode achieves a high area capacity of 8.4 mAh cm−2, a high rate capacity of up to 2 C and an excellent cycle capacity of over 400 cycles. Image 1 • Nanofibers with high electrical and ion conductivity are synthesized. • The doped CeO 2 nanocrystals have high electrocatalytic activity. • The CeO 2 @CNF electrodes exhibits good electrochemical performance. [ABSTRACT FROM AUTHOR]

Minimizing the shuttle effect of polysulfides (PS) is crucial for practical applications of lithium-sulfur (Li-S) batteries. However, the trade-off between effective suppression of the shuttle effect and fast redox reaction kinetics is inevitable for separator-based Li-S batteries. Herein, via a self-confined solid-conversion process, we develop a polystyrene sulfonate (PSS)-threaded well-intergrown HKUST-1 (Cu 3 (BTC) 2 ) (BTC: 1,3,5-benzenetricarboxylic acid)-coated Celgard separator (PSS@HKUST-1/Celgard, PHC) for high-performance Li-S batteries. The PHC membrane favors the interception and accommodation of long-chain PS. Notably, enormous sulfonate groups of the three-dimensional PSS networks in PSS@HKUST-1 membrane significantly facilitate lithium-ion transport, which guarantee fast redox kinetics. The PHC separator demonstrates efficient inhibition of PS (i.e., 4 orders of magnitude lower in PS permeation rate) with fast Li + transportation (i.e., 71% higher in ionic conductivity) than the Celgard separator. When applying the PHC membrane in Li-S batteries with conventional sulfur/super P carbon cathode, highly reversible capacity with an average fading rate of 0.05% per cycle is maintained for 500 cycles at 0.5 C, excellent rate performance up to 5 C, and high areal capacity over 7 mA h cm -2 are also achieved. This work paves a new way for addressing the trade-off between suppressing the PS shuttle effect and fast kinetic reaction for separator-based Li-S batteries.