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1.
Angew Chem Int Ed Engl ; 62(30): e202303048, 2023 Jul 24.
Article En | MEDLINE | ID: mdl-37249478

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2 ) into multi-carbon (C2+ ) products involving C-C coupling. Herein we report a single-atomic Bi decorated Cu alloy (denoted as BiCu-SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu-SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles-decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm-2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu-SAA is found to favor the activation of CO2 and subsequent C-C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity.

2.
Psych J ; 12(4): 547-560, 2023 Aug.
Article En | MEDLINE | ID: mdl-37220758

Negativity bias refers to the phenomenon whereby people put more weight on negative information. Although evolutionarily favorable for survival, negative bias in impression processing is detrimental to relationships and cooperation. To explore whether the motivation to maintain relationships, indicated by self-construal, mitigates negativity bias, two studies were conducted. In study 1, participants interacted with three agents (worsened, improved, baseline) in a modified social learning task and evaluated the moral level of these agents. Results showed that positivity bias appeared among interdependent individuals, with larger updating for the improved agent than for the worsened agent. Moreover, interdependent individuals exhibited less immediate decreases toward the worsened agent and steeper increases toward the improved agent than did independent individuals. To validate the results of study 1, we used a narrative description paradigm in study 2. Participants read the behavior descriptions of agents and rated them on morality. The negativity bias was significantly mitigated among individuals with high interdependence, though it did not reverse. These results indicate that interdependent individuals focus more on positive information when others change, yielding a more positive pattern in impression updating. This flexible interpersonal coping strategy can bring advantages to social interaction and cooperation.


Motivation , Self Concept , Humans , Adaptation, Psychological
3.
J Am Chem Soc ; 144(39): 18144-18152, 2022 Oct 05.
Article En | MEDLINE | ID: mdl-36135972

Fe-N-C electrocatalysts have emerged as promising substitutes for Pt-based catalysts for the oxygen reduction reaction (ORR). However, their real catalytic active site is still under debate. The underlying roles of different types of coordinating N including pyridinic and pyrrolic N in catalytic performance require thorough clarification. In addition, how to understand the pH-dependent activity of Fe-N-C catalysts is another urgent issue. Herein, we comprehensively studied 13 different N-coordinated FeNxC configurations and their corresponding ORR activity through simulations which mimic the realistic electrocatalytic environment on the basis of constant-potential implicit solvent models. We demonstrate that coordinating pyrrolic N contributes to a higher activity than pyridinic N, and pyrrolic FeN4C exhibits the highest activity in acidic media. Meanwhile, the in situ active site transformation to *O-FeN4C and *OH-FeN4C clarifies the origin of the higher activity of Fe-N-C in alkaline media. These findings can provide indispensable guidelines for rational design of better durable Fe-N-C catalysts.

4.
Neuropsychologia ; 172: 108274, 2022 07 29.
Article En | MEDLINE | ID: mdl-35623449

The ability to control unwanted memories is essential for emotional regulation and maintaining mental health. Previous evidence indicates that suppressing retrieval, which recruits executive control mechanisms to prevent unwanted memories entering consciousness, can cause forgetting, termed suppression-induced forgetting (SIF). Since these executive mechanisms involve multiple mental operations, we hypothesize that the efficacy of SIF may be limited by individuals' capacity limitation of cognitive control. Here, we tested this hypothesis. Participants were assigned to two groups based on the median of their cognitive control capacity (CCC, estimated by the backward masking majority function task) and performed the think/no-think task with electrophysiological signals recorded. The results showed that the SIF effect was observed only in the high CCC group but not in the low CCC group. In accordance, repeated suppression attempts also resulted in a steeper reduction in intrusive thoughts in the high CCC group. Furthermore, ERP analysis revealed a decrease in recollection-related late parietal positivity (LPP) under the no-think condition in the high CCC group. A mediation analysis revealed that the reduced intrusive memories mediated the effect of CCC on SIF. These findings suggest that suppressing retrieval could reduce traces of the unwanted memories, making them less intrusive and harder to recall. More importantly, successful SIF is constrained by the capacity of cognitive control which may be used to ensure the coordination of multiple cognitive processes during suppression.


Cognition , Mental Recall , Cognition/physiology , Executive Function , Humans , Mental Recall/physiology
5.
J Oral Rehabil ; 46(12): 1192-1203, 2019 Dec.
Article En | MEDLINE | ID: mdl-31295755

The aim of this systematic review was to compare the survival rate, marginal bone loss changes and complications between short implants (5-8 mm) and long implants (≥10 mm) with a bone-augmented procedure in the posterior jaw. An electronic search of the MEDLINE (PubMed), Embase and Cochrane Library databases through September 2018 was done to identify randomised controlled trials (RCT) assessing short implants and long implants with at least a 1-year follow-up period after loading. A quantitative meta-analysis was conducted on the survival rate, marginal bone loss changes and complications. Ten RCTs met the inclusion criteria. There were no significant differences in the survival rate (RR: 1.01; 95% CI: [0.99, 1.03]; P = .32) and complications (RR: 0.48; 95% CI: [0.20, 1.17]; P = .11) between the two groups. Compared with the long implant group, the short implant group had a lower marginal bone loss change, and the effect measure was significant (mean difference: -0.13; 95% CI: [-0.20, -0.06]; P < .05). This systematic review showed no difference between the survival rates and complications of short implants (5-8 mm) and long implants (≥10 mm). The marginal bone loss changes in short implants are lower than those in long implants.


Alveolar Ridge Augmentation , Dental Implants , Dental Implantation, Endosseous , Dental Prosthesis Design , Dental Prosthesis, Implant-Supported , Dental Restoration Failure , Humans , Randomized Controlled Trials as Topic
6.
Implant Dent ; 28(6): 578-589, 2019 Dec.
Article En | MEDLINE | ID: mdl-31205270

BACKGROUND: During implantation planning, dentists should be able to make an informed decision regarding whether to use an implant template to assist the surgery. PURPOSE: The aim of this meta-analysis was to assess the results of implantation with or without an implant template based on the accuracy, survival rate, and other considerations. MATERIALS AND METHODS: In January 2018, a systematic review was undertaken for randomized controlled trials and retrospective and prospective cohort studies with relevance to implant accuracy and the survival rate between the implant template and free-hand method. The odds ratios (ORs) of the survival rate and the mean difference of accuracy deviation from the selected papers were estimated by meta-analysis. RESULTS: Of the 362 screened articles, 6 studies were included in the meta-analysis. Comparison of the survival rate of implant surgery with or without an implant template revealed no significant result (OR = 1.71, 95% confidence interval [CI] 0.65-4.51). Significant differences in accuracy were observed in angular (mean difference = -5.45 degrees, 95% CI -0.66 to -4.24 degrees) and apical deviation (mean difference = -0.83 mm, 95% CI -1.12 to -0.54). CONCLUSIONS: With the technology of computer-aided surgical template, implant placement can be more accurate than free-hand operation. No significant difference is observed in the survival rate between template and free-hand.


Dental Implants , Surgery, Computer-Assisted , Computer-Aided Design , Dental Implantation, Endosseous , Patient Care Planning , Prospective Studies , Retrospective Studies
7.
Exp Ther Med ; 8(4): 1047-1054, 2014 Oct.
Article En | MEDLINE | ID: mdl-25187795

The aim of the present study was to compare the root canal preparation ability of rotary nickel-titanium (NiTi) Hero 642 and K3 files in curved mandibular or maxillary molars. A total of 40 extracted mandibular molars with two separate mesial canals, an apical width of approximately size ≤15 and a root canal curvature of 15-30° were randomly divided into two groups and instrumented using Hero 642 (n=20) or K3 files (n=20). Canal straightening, working length, transportation, cross-sectional area, minimum dentin thickness and the canal angle curvature degree were examined, and a systematic review of the literature was conducted. No statistically significant differences were observed between the two groups with regard to the mean degree of straightening, mean change in working length, mean transportation, amount of dentin removed or remaining minimum dentin thickness (P>0.05). The canal angle curvature decreased in the two groups postoperatively. The systematic review identified six studies, and overall the two files performed similarly in the majority of categories examined. Therefore, the rotary NiTi Hero 642 and K3 files demonstrated comparable shaping abilities and maintenance of working length.

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