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Integration of graphene-like carbon nitride materials is essential for nanoelectronic applications.

In order to explore the intrinsic properties of single-atom (SA) catalysts, the different kinds of coordinated atoms (typically Bx and Ny) within graphene (BxNy–graphene, x + y = 1–3) can be used to regulate the stability and electronic structure of center metal SAs (BxNy–graphene-SAs) by density functional theory (DFT) calculations. It is found that the SA Co anchored at single vacancy graphene (SV-graphene–Co), B1–graphene–Co and N1–graphene–Co configurations exhibit higher stability than others. The amount of charge transfer between coordinated BxNy and nearest-neighbor carbon atoms can effectively modulate the adsorption stabilities, electronic structures and magnetic properties of central Co atom and reactive gases. Compared to the SV-graphene–Co sheet, the formation of BxNy–graphene sheets can promote the adsorption capabilities for NO and CO; further, the NO and CO oxidation reactions through the Eley–Rideal (ER) and Langmuir–Hinshelwood (LH) mechanisms are comparably investigated. Among these different ratios of coordinated BxNy atoms, the B1–graphene–Co, N1–graphene–Co and B1N1–graphene–Co sheets exhibit good stability and show excellent catalytic activity (

With the development of cutting-edge technology in the area of driving performance, driver warning systems based on head up displays (HUD) are considered to have the potential to improve driving sa...

PIEZO1 is a non-selective cation channel protein that converts mechanical stimuli into electrochemical signals through mechanical force transmission. In recent years, more and more attention has been paid to its relationship with cardiovascular development and related diseases. However, PIEZO1 is difficult to be used as a therapeutic target due to incomplete study of its related phenotype and mechanism. Starting with the phenotypes of zebrafish at different stages of development, piezo1 knockout zebrafish features decreased heart rate in embryonic stage, increased heart size in 72dpf larvae, as well as ventricular enlargement, passivation and increased immune infiltration in adult stage. Further characterization revealed the relationship between PIEZO1 and AcanA protein at embryonic stage, and hand2 protein at adult stage. Through further RNA-seq analysis, ptpn21 downregulation, shox2 upregulation, itga4 upregulation were used to explain ventricular enlargement, heart rate decrease and immune infiltration increase respectively. Overall, this study provides a theoretical basis for elucidating the mechanism of PIEZO1 in regulating cardiac development.

Single-atom catalysts (SACs) are of great scientific and technical importance due to their low cost, high site density, and high specificity to enhance chemical reactions. Nevertheless, a major issue that severely limits the practical exploration of SACs is their instability, i.e., the preference of sintering and clustering over a defect-free substrate during operation. Here, we employ first-principles calculations to investigate how substrate engineering can stabilize SACs by strain-tuning the electronic interactions between the metal and the substrate using two Pd adatoms on a defect-free, single-layer MoS2 as a typical example. It is identified that the Pd2 dimer is prone to dissociate and form highly efficient SACs for CO oxidation due to the enhanced charge transfer and orbital hybridization with the MoS2 substrate under a suitable tensile strain. The straining induces a semiconductive-to-metallic phase transition of the substrate. Moreover, low-cost elements, such as Ag, Ni, Cu, and Cr, can also be stabilized into high-performance SACs for CO oxidation with tunable reaction barriers by straining. The present findings offer a new avenue to inhibit the transition metal atoms from clustering into nanoclusters/particles and provide a clear guidance for the development of highly cost-efficient and stable SACs on defect-free substrates.

This study aims to investigate the benefits of unimodal tactile displays relative to other modal displays and the performance gains of adding redundant tactile displays by integrating empirical studies.Tactile displays have attracted increasing attention in recent years due to their unique advantages. Synthesizing experimental data is necessary to analyze the performance benefits of tactile displays for participants and better help practitioners in utilizing them.Five meta-analyses were conducted. Two meta-analyses compared the participants' performance between tactile and other modal displays (visual vs. tactile and auditory vs. tactile). Three meta-analyses examined the performance gains of adding redundant tactile displays based on other modal displays (visual vs. visual + tactile, auditory vs. auditory + tactile, and visual + auditory vs. visual + auditory + tactile). The related moderator variables, the types of presented information and concurrent tasks, were analyzed.Little evidence shows the performance difference between tactile and auditory displays. Tactile displays are more beneficial than visual displays for presenting alert information or in the situation with a visual concurrent task. The performance gains of adding redundant tactile displays to other modal displays also depend on the specific type of presented information and the concurrent task.When using tactile displays to convey information, interface designers should consider the specific type of presented information and the concurrent tasks.The present study's findings can provide some implications for designers to utilize tactile displays when they construct and implement information displays.

Design is an iterative process that aims at problem-solving. While the importance of mental iteration has been identified, there are little research on how to improve mental iteration in design process. In this paper, we propose a method to augment design by AI. An experiment was conducted to study the effect of AI augment on design iteration. The results indicate AI augment could improve the designers’ performance in fluency and stylization.

In this paper, we investigate the impact of music exposure on novice designers’ creativity performance. We found that compared to without-music, exposure to fast-tempo music significantly improved their ideas’ fluency and flexibility. These results indicate that exposure to fast-tempo music can enhance novice designers’ performance on design tasks. As a low-cost and convenient way of promoting creative thinking, music could use in creativity education and training.

Conditional automated driving [level 3, Society of Automotive Engineers (SAE)] requires drivers to take over the vehicle when an automated system’s failure occurs or is about to leave its operational design domain. Two-stage warning systems, which warn drivers in two steps, can be a promising method to guide drivers in preparing for the takeover. However, the proper time intervals of two-stage warning systems that allow drivers with different personalities to prepare for the takeover remain unclear. This study explored the optimal time intervals of two-stage warning systems with insights into the drivers’ neuroticism personality. A total of 32 drivers were distributed into two groups according to their self-ratings in neuroticism (high vs. low). Each driver experienced takeover under the two-stage warning systems with four time intervals (i.e., 3, 5, 7, and 9 s). The takeover performance (i.e., hands-on-steering-wheel time, takeover time, and maximum resulting acceleration) and subjective opinions (i.e., appropriateness and usefulness) for time intervals and situation awareness (SA) were recorded. The results showed that drivers in the 5-s time interval had the best takeover preparation (fast hands-on steering wheel responses and sufficient SA). Furthermore, both the 5- and 7-s time intervals resulted in more rapid takeover reactions and were rated more appropriate and useful than the 3- and 9-s time intervals. In terms of personality, drivers with high neuroticism tended to take over immediately after receiving takeover messages, at the cost of SA deficiency. In contrast, drivers with low neuroticism responded safely by judging whether they gained enough SA. We concluded that the 5-s time interval was optimal for drivers in two-stage takeover warning systems. When considering personality, drivers with low neuroticism had no strict requirements for time intervals. However, the extended time intervals were favorable for drivers with high neuroticism in developing SA. The present findings have reference implications for designers and engineers to set the time intervals of two-stage warning systems according to the neuroticism personality of drivers.

In conditional automated driving (SAE Level 3), drivers are required to take over their vehicles when the automated systems fail. Non-driving related tasks (NDRTs) can positively or negatively affect takeover safety, but the underlying reasons for this inconsistency remain unclear. This study aims to investigate how various workload levels generated by NDRTs may influence the takeover performance of drivers and the lead time they require. Fifty drivers were randomly distributed into five groups, which corresponded to five workload levels (1-4 levels generated by Tetris game; control level generated by monitoring). Each driver completed vehicle takeover tasks upon receiving takeover requests with various lead times (3, 5, 7, 9, and 11 s) while engaging in NDRTs. The drivers’ takeover performance and subjective opinions were recorded. Drivers in the moderate workload condition (i.e., level 3) had significantly shorter takeover times and better takeover quality than those in the lower (i.e., level 1 and level 2) or higher (i.e., level 4) workload conditions. They also subjectively required less lead time in the moderate condition. Moreover, the drivers rated 7 s as the most appropriate lead time despite the improvement in their overall takeover performances with increased lead time. This study found an inverted U-shaped relationship between the drivers’ workload generated by NDRTs and takeover performance. The moderate workload level (rather than the lower or higher workload level) led to a faster and better takeover performance, and it seemed to require minimal lead time for drivers. These findings help understand the relationship of drivers’ workload during the automation and takeover performance in conditional automated driving. An important recommendation emerging from this work is to investigate what should be the most efficient method to detect the drivers’ workload state real-time and give feedback to them when it comes to overload or underload during the automated driving.

The formation geometry, electronic property and catalytic activity of single-atom (SAs) Fe anchored graphene with different kinds and number of coordinated B and N atoms (xB-yN-graphene-SAs, x + y = 1–3) are comparably investigated by using the density functional theory (DFT) calculations. It is found that the coordinated 1B, 1 N, 2B–1N atoms can more effectively control the stability of SAs Fe on graphene sheet than other coordination structures, and these formation configurations exhibit the high thermal stability. Among these xB-yN-graphene-Fe sheets, the formation of 3N-graphene-Fe exhibits the high gas sensoring for the single gas molecule and coadsorbed gas reactants. Meanwhile, these gas adsorbed systems exhibit the various electronic and magnetic properties by promoting the charge transfer between adsorbates and substrates. By investigation the Langmuir-Hinshelwood (LH) and Eley-Rideal (ER) mechanisms for NO and CO oxidations, the 1B–1N-graphene-Fe and 1B-graphene-Fe sheets exhibit the more activity (

This study aims to investigate the usability of a head-up display (HUD) in presenting warning messages during driving and create a new and effective vehicle early warning system for drivers. Two ex...

Road rage has a series of adverse effects on driving safety, and many accidents caused by road rage occur in China. Thus, understanding the pattern of road rage has great significance to driving safety. In the present study, 33 video news was evaluated subjectively on the severity of road rage and environmental variables, the gender of drivers and the dimension of inducing events were coded according to the video. The results revealed that the road rage was more serious when the number of lanes was lower, and the rage vehicle and offensive vehicle were non-motorized vehicles. There were more cars and fewer non-motor vehicles in road rage during the daytime and fewer angry trucks in the urban areas. On the highway, the vehicles in rage involve more trucks and fewer cars. Moreover, drivers of cars were more likely to do discourteous offensive behavior and drivers of the non-motor vehicles were more likely to do slow-driving behavior. These findings can be applied to the design of intelligent transportation systems and the education of drivers to relieve road rage.

Single-atom catalysts (SACs) are of great scientific and technical importance due to their low cost, high site density, and high specificity to enhance chemical reactions. Nevertheless, a major issue that severely limits the practical exploration of SACs is their instability, i.e., the preference of sintering and clustering over a defect-free substrate during operation. Here, we employ first-principles calculations to investigate how substrate engineering can stabilize SACs by strain-tuning the electronic interactions between the metal and the substrate using two Pd adatoms on a defect-free, single-layer MoS

According to the assembly task model proposed by Stork and Schubö (2010), the assembly task is divided into commissioning and joining subtasks. Each subtask includes two sequential stages, namely, perception and response selection, and action. This division enables a convenient discussion of the influences of Augmented reality (AR) assistance on operators during different stages of an assembly task. Research results can provide a basis for the further analysis of the influence mechanism of AR assistance on an assembly task. This study is composed of three experiments. Experiment 1 explores the influences of AR assistance on the performance of the overall assembly task and the commissioning and joining subtasks. Combining a variation of task complexities, Experiments 2 and 3 discuss the influences of AR assistance on the different stages of the commissioning and joining subtasks. We found that AR assistance can shorten the time of the overall assembly task and subtasks (commissioning and joining) and reduce mistakes during these tasks. Moreover, AR assistance can decrease cognitive load in the commissioning subtask, but it increases cognitive load in the joining task with low complexity. In the perception and response selection stage of the commissioning and joining subtasks, AR assistance can shorten the time for users to recognize the target part and understand the assembly relation. This advantage is extremely significant for the high-complexity task. In the action stage of two subtasks, AR assistance can shorten the time for users to capture parts, but it prolongs the time for users to build parts.

The different genome-wide distributions of tri-methylation at H3K36 (H3K36me3) in various species suggest diverse mechanisms for H3K36me3 establishment during evolution. Here, we show that the transcription factor OsSUF4 recognizes a specific 7-bp DNA element, broadly distributes throughout the rice genome, and recruits the H3K36 methyltransferase SDG725 to target a set of genes including the key florigen genes RFT1 and Hd3a to promote flowering in rice. Biochemical and structural analyses indicate that several positive residues within the zinc finger domain are vital for OsSUF4 function in planta. Our results reveal a regulatory mechanism contributing to H3K36me3 distribution in plants., The distribution of H3K36me3 varies between species. Here Liu et al. show that the OsSUF4 transcription factor binds its target motif via a zinc finger domain to promote H3K36 methyltransferase targeting close to the transcription start site of genes including the flowering regulators RFT1 and Hd3a.

Egocentric distance perception refers to the perception of distance from a target to a perceiver, which is an important component of visual space perception. It is important to activities in virtual environments and influenced by several factors, such as action capacities and visual cues. However, few studies have investigated such aspects. Hence, Experiments 1 and 2 investigated the effect of using experience and visual cues, respectively, of virtual arms on egocentric distance perception in near and far spaces at equal, prolonged, and shortened lengths of a virtual arm. Results revealed that using experience and visual cues of the virtual arm had a significant effect on egocentric distance perception when the length of virtual arm was equal to the real arm and prolonged but not when shortened. The egocentric distance perception on the conditions of having using experience and virtual arm was most precise. The findings provide implications for the design and implementation of virtual body self-representation in virtual environments.

Background Intron retention (IR), the most prevalent alternative splicing form in plants, plays a critical role in gene expression during plant development and stress response. However, the molecular mechanisms underlying IR regulation remain largely unknown. Results Knockdown of SDG725, a histone H3 lysine 36 (H3K36)-specific methyltransferase in rice, leads to alterations of IR in more than 4700 genes. Surprisingly, IR events are globally increased at the 5′ region but decreased at the 3′ region of the gene body in the SDG725-knockdown mutant. Chromatin immunoprecipitation sequencing analyses reveal that SDG725 depletion results in a genome-wide increase of the H3K36 mono-methylation (H3K36me1) but, unexpectedly, promoter-proximal shifts of H3K36 di- and tri-methylation (H3K36me2 and H3K36me3). Consistent with the results in animals, the levels of H3K36me1/me2/me3 in rice positively correlate with gene expression levels, whereas shifts of H3K36me2/me3 coincide with position-specific alterations of IR. We find that either H3K36me2 or H3K36me3 alone contributes to the positional change of IR caused by SDG725 knockdown, although IR shift is more significant when both H3K36me2 and H3K36me3 modifications are simultaneously shifted. Conclusions Our results revealed that SDG725 modulates IR in a position-specific manner, indicating that H3K36 methylation plays a role in RNA splicing, probably by marking the retained introns in plants. Electronic supplementary material The online version of this article (10.1186/s12915-018-0513-8) contains supplementary material, which is available to authorized users.

Lysozymes are known as ubiquitously distributed immune effectors with hydrolytic activity against peptidoglycan, the major bacterial cell wall polymer, to trigger cell lysis. In the present study, the full-length cDNA sequence of a novel sea urchin Strongylocentrotus purpuratus invertebrate-type lysozyme (sp-iLys) was synthesized according to the codon usage bias of Pichia pastoris and was cloned into a constitutive expression plasmid pPIC9K. The resulting plasmid, pPIC9K-sp-iLys, was integrated into the genome of P. pastoris strain GS115. The bioactive recombinant sp-iLys was successfully secreted into the culture broth by positive transformants. The highest lytic activity of 960 U/mL of culture supernatant was reached in fed-batch fermentation. Using chitin affinity chromatography and gel-filtration chromatography, recombinant sp-iLys was produced with a yield of 94.5 mg/L and purity of > 99%. Recombinant sp-iLys reached its peak lytic activity of 8560 U/mg at pH 6.0 and 30 °C and showed antimicrobial activities against Gram-negative bacteria (Vibrio vulnificus, Vibrio parahemolyticus, and Aeromonas hydrophila) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis). In addition, recombinant sp-iLys displayed isopeptidase activity which reached the peak at pH 7.5 and 37 °C with the presence of 0.05 M Na+. In conclusion, this report describes the heterologous expression of recombinant sp-iLys in P. pastoris on a preparative-scale, which possesses lytic activity and isopeptidase activity. This suggests that sp-iLys might play an important role in the innate immunity of S. purpuratus.

Figure S1. The quantification of H3K36 methylation in 725Ri-1. and WT plants. Figure S2. Differential gene expression between 725Ri-1. and WT rice. Figure S3. Accumulative plot of up-regulated (725Ri-1._IRI_up) and down-regulated (725Ri-1._IRI_down) IR events with different intron length coverage. Figure S4. Distribution of up-regulated (red.) and down-regulated (blue.) intron retention (IR) events between 725Ri-1. and wild-type (WT) rice (a) and between 708Ri-1. and WT (b). Figure S5. Schematic diagram illustrating the way to transform the H3K36 methylation changes between the 725Ri-1. and wild-type plants at individual gene level. Figure S6. Box plot for levels of H3K36 methylations at IRI-up or IRI-down introns. Figure S7. qPCR validation of quality of cellular fractionation in wild-type rice. Figure S8. Box plot for expression level of transcripts with premature termination codon. Figure S9. Box plot of gene expression before and after cycloheximide (CHX) treatment in either wild-type or 725Ri-1. rice. Figure S10. H3K36 methylations associate with gene expression levels. Figure S11. Distribution of up-regulated (red.) and down-regulated (blue.) intron retention (IR) events in genes with no obvious changes (≤ 2-fold) in total levels of H3K36me2 (a) or H3K36me3 (b). Figure S12. Box plot for intron length in two groups of introns by distinct methods in calculating the degree of intron retention. Figure S13. Box plot for GC percentage in two groups of introns. Figure S14. Box plot for maximum entropy score of 5′ splice site (a) and 3′ splice site (b) in two groups of introns. Figure S15. Comparison of H3K36me2/me3 distribution across gene body between rice (a) and Arabidopsis (b). (DOCX 2596 kb)

Exploration of the catalytic activity of low-dimensional transition metal (TM) or noble metal catalysts is a vital subject of modern materials science because of their instrumental role in numerous industrial applications. Recent experimental advances have demonstrated the utilization of single atoms on different substrates as effective catalysts, which exhibit amazing catalytic properties such as more efficient catalytic performance and higher selectivity in chemical reactions as compared to their nanostructured counterparts; however, the underlying microscopic mechanisms operative in these single atom catalysts still remain elusive. Based on first-principles calculations, herein, we present a comparative study of the key kinetic rate processes involved in CO oxidation using a monomer or dimer of two representative TMs (Pd and Ni) on defective TiO2(110) substrates (TMn@TiO2(110), n = 1, 2) to elucidate the underlying mechanism of single-atom catalysis. We reveal that the O2 activation rates of the single atom TM catalysts deposited on TiO2(110) are governed cooperatively by the classic spin-selection rule and the well-known frontier orbital theory (or generalized d-band picture) that emphasizes the energy gap between the frontier orbitals of the TM catalysts and O2 molecule. We further illuminate that the subsequent CO oxidation reactions proceed via the Langmuir–Hinshelwood mechanism with contrasting reaction barriers for the Pd monomer and dimer catalysts. These findings not only provide an explanation for existing observations of distinctly different catalytic activities of Pd@TiO2(110) and Pd2@TiO2(110) [Kaden et al., Science, 2009, 326, 826–829] but also shed new insights into future utilization and optimization of single-atom catalysis.