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1.
Nucleic Acids Res ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319582

RESUMO

Non-canonical nucleic acid structures, such as G-quadruplex (G4) and i-Motif (iM), have garnered significant research interest because of their unique structural properties and biological activities. Thousands of small molecules targeting G4/iM structures have been developed for various chemical and biological applications. In response to the growing interest in G4-targeting ligands, we launched the first G4 Ligand Database (G4LDB) in 2013. Here, we introduce G4LDB 3.0 (http://www.g4ldb.com), an upgraded version featuring extensive enhancements in content and functionality. The new version includes over 4800 G4/iM ligands and approximately 51 000 activity entries. Key upgrades include advanced search capabilities, dynamic knowledge graphs, enhanced data visualization, along with a new dynamic analysis function that automatically displays ligand structure clustering results and chemical space distribution. With these updates, G4LDB 3.0 further evolves into a comprehensive resource and valuable research tool. The significant improvements address the increasing demand for efficient data handling and user experience, highlighting the critical role of G4LDB in advancing research on G-quadruplexes and i-motifs.

2.
Plant Physiol ; 195(2): 958-969, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38447074

RESUMO

The fruit neck is an important agronomic trait of cucumber (Cucumis sativus). However, the underlying genes and regulatory mechanisms involved in fruit neck development are poorly understood. We previously identified a cucumber yellow-green peel (ygp) mutant, whose causal gene is MYB DOMAIN PROTEIN 36 (CsMYB36). This study showed that the ygp mutant exhibited a shortened fruit neck and repressed cell expansion in the fruit neck. Further functional analysis showed that CsMYB36 was also a target gene, and its expression was enriched in the fruit neck. Overexpression of CsMYB36 in the ygp mutant rescued shortened fruit necks. Furthermore, transcriptome analysis and reverse transcription quantitative PCR (RT-qPCR) assays revealed that CsMYB36 positively regulates the expression of an expansin-like A3 (CsEXLA3) in the fruit neck, which is essential for cell expansion. Yeast 1-hybrid and dual-luciferase assays revealed that CsMYB36 regulates fruit neck elongation by directly binding to the promoter of CsEXLA3. Collectively, these findings demonstrate that CsMYB36 is an important gene in the regulation of fruit neck length in cucumber plants.


Assuntos
Cucumis sativus , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
3.
Nano Lett ; 24(20): 5984-5992, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38728101

RESUMO

Addressing the need for modulated spin configurations is crucial, as they serve as the foundational building blocks for next-generation spintronics, particularly in atomically thin structures and at room temperature. In this work, we realize intrinsic ferromagnetism in monolayer flakes and tunable ferro-/antiferromagnetism in (Fe0.56Co0.44)5GeTe2 antiferromagnets. Remarkably, the ferromagnetic ordering (≥1 L) and antiferromagnetic ordering (≥4 L) remain discernible up to room temperature. The TC (∼310 K) of the monolayer flakes sets a record high for known exfoliated monolayer van der Waals magnets. Within the framework of A-type antiferromagnetism, a notable odd-even layer-number effect at elevated temperatures (T = 150 K) is observed. Of particular interest is the strong ferromagnetic order in even-layer flakes at low temperatures. The intricate interplay among magnetic field strength, layer number, and temperature gives rise to a diverse array of phenomena, holding promise not only for new physics but also for practical applications.

4.
J Neurosci ; 43(49): 8456-8471, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37852791

RESUMO

Interpersonal emotion regulation is the dynamic process where the regulator aims to change the target's emotional state, which is presumed to engage three neural systems: cognitive control (i.e., dorsal and ventral lateral PFC, etc.), empathy/social cognition (i.e., dorsal premotor regions, temporal-parietal junction, etc.), and affective response (i.e., insula, amygdala, etc.). This study aimed to identify the underlying neural correlate (especially the interpersonal one), of interpersonal emotion regulation based on two typical strategies (cognitive appraisal, expressive suppression). Thirty-four female dyads (friends) were randomly assigned into two strategy groups, with one assigned as the target and the other as the regulator to downregulate the target's negative emotions using two strategies. A functional near-infrared spectroscopy system was used to simultaneously measure participants' neural activity. Results showed that these two strategies could successfully downregulate the targets' negative emotions. Both strategies evoked intrapersonal and interpersonal neural couplings between the cognitive control, social cognition, and mirror neuron systems (e.g., PFC, temporal-parietal junction, premotor cortex, etc.), whereas cognitive reappraisal (vs expressive suppression) evoked a broader pattern. Further, cognitive reappraisal involved increased interpersonal brain synchronization between the prefrontal and temporal areas at the sharing stage, whereas expressive suppression evoked increased interpersonal brain synchronization associated with the PFC at the regulation stage. These findings indicate that intrapersonal and interpersonal neural couplings associated with regions within the abovementioned systems, possibly involving mental processes, such as cognitive control, mentalizing, and observing, underlie interpersonal emotion regulation based on cognitive reappraisal or expressive suppression.SIGNIFICANCE STATEMENT As significant as intrapersonal emotion regulation, interpersonal emotion regulation subserves parent-child, couple, and leader-follower relationships. Despite enormous growth in research on intrapersonal emotion regulation, the field lacks insight into the neural correlates underpinning interpersonal emotion regulation. This study aimed to probe the underlying neural correlates of interpersonal emotion regulation using a multibrain neuroimaging (i.e., hyperscanning) based on functional near-infrared spectroscopy. Results showed that both cognitive reappraisal and expressive suppression strategies successfully downregulated the target's negative emotions. More importantly, they evoked intrapersonal and interpersonal neural couplings associated with regions within the cognitive control, social cognition, and mirror neuron systems, possibly involving mental processes, such as cognitive control, mentalizing, and observing. These findings deepen our understanding of the neural correlates underpinning interpersonal emotion regulation.


Assuntos
Regulação Emocional , Feminino , Humanos , Encéfalo/fisiologia , Mapeamento Encefálico , Cognição/fisiologia , Emoções/fisiologia , Imageamento por Ressonância Magnética
5.
Plant J ; 116(2): 524-540, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37460197

RESUMO

To improve our understanding of the mechanism underlying cucumber glossiness regulation, a novel cucumber mutant with a glossy peel (Csgp) was identified. MutMap, genotyping, and gene editing results demonstrated that CsSEC23, which is the core component of COPII vesicles, mediates the glossiness of cucumber fruit peel. CsSEC23 is functionally conserved and located in the Golgi and endoplasmic reticulum. CsSEC23 could interact with CsSEC31, but this interaction was absent in the Csgp mutant, which decreased the efficiency of COPII vesicle transportation. Genes related to wax and cutin transport were upregulated in the Csgp mutant, and the cuticle structure of the Csgp-mutant peel became thinner. Moreover, the wax and cutin contents were also changed due to CsSEC23 mutation. Taken together, the results obtained from this study revealed that CsSEC23 mediates cucumber glossiness, and this mediating might be affected by COPII vesicle transportation.

6.
J Am Chem Soc ; 146(2): 1244-1249, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38180816

RESUMO

Superconductivity was discovered in (InSe2)xNbSe2. The materials are crystallized in a unique layered structure where bonded InSe2 layers are intercalated into the van der Waals gaps of 2H-phase NbSe2. The (InSe2)0.12NbSe2 superconductor exhibits a superconducting transition at 11.6 K and critical current density of 8.2 × 105 A/cm2. Both values are the highest among all transition metal dichalcogenide superconductors at ambient pressure. The present finding provides an ideal material platform for further investigation of superconducting-related phenomena in transition metal dichalcogenides.

7.
Plant Biotechnol J ; 22(6): 1724-1739, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38261466

RESUMO

Increased planting densities boost crop yields. A compact plant architecture facilitates dense planting. However, the mechanisms regulating compact plant architecture in cucurbits remain unclear. In this study, we identified a cucumber (Cucumis sativus) compact plant architecture (cpa1) mutant from an ethyl methane sulfonate (EMS)-mutagenized library that exhibited distinctive phenotypic traits, including reduced leaf petiole angle and leaf size. The candidate mutation causes a premature stop codon in CsaV3_1G036420, which shares similarity to Arabidopsis HOOKLESS 1 (HLS1) encoding putative histone N-acetyltransferase (HAT) protein and was named CsHLS1. Consistent with the mutant phenotype, CsHLS1 was predominantly expressed in leaf petiole bases and leaves. Constitutive overexpressing CsHLS1 in cpa1 restored the wild-type plant architecture. Knockout of CsHLS1 resulted in reduces leaf petiole angle and leaf size and as well as decreased acetylation levels. Furthermore, CsHLS1 directly interacted with CsSCL28 and negatively regulated compact plant architecture in cucumber. Importantly, CsHLS1 knockout increased the photosynthesis rate and leaf nitrogen in cucumbers, thereby maintaining cucumber yield at normal density. Overall, our research provides valuable genetic breeding resource and gene target for creating a compact plant architecture for dense cucumber planting.


Assuntos
Cucumis sativus , Folhas de Planta , Proteínas de Plantas , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/anatomia & histologia , Cucumis sativus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas , Fotossíntese/genética , Mutação , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo
8.
Microb Cell Fact ; 23(1): 58, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383407

RESUMO

Acetoin, a versatile platform chemical and popular food additive, poses a challenge to the biosafety strain Bacillus subtilis when produced in high concentrations due to its intrinsic toxicity. Incorporating the PHB synthesis pathway into Bacillus subtilis 168 has been shown to significantly enhance the strain's acetoin tolerance. This study aims to elucidate the molecular mechanisms underlying the response of B. subtilis 168-phaCBA to acetoin stress, employing transcriptomic and metabolomic analyses. Acetoin stress induces fatty acid degradation and disrupts amino acid synthesis. In response, B. subtilis 168-phaCBA down-regulates genes associated with flagellum assembly and bacterial chemotaxis, while up-regulating genes related to the ABC transport system encoding amino acid transport proteins. Notably, genes coding for cysteine and D-methionine transport proteins (tcyB, tcyC and metQ) and the biotin transporter protein bioY, are up-regulated, enhancing cellular tolerance. Our findings highlight that the expression of phaCBA significantly increases the ratio of long-chain unsaturated fatty acids and modulates intracellular concentrations of amino acids, including L-tryptophan, L-tyrosine, L-leucine, L-threonine, L-methionine, L-glutamic acid, L-proline, D-phenylalanine, L-arginine, and membrane fatty acids, thereby imparting acetoin tolerance. Furthermore, the supplementation with specific exogenous amino acids (L-alanine, L-proline, L-cysteine, L-arginine, L-glutamic acid, and L-isoleucine) alleviates acetoin's detrimental effects on the bacterium. Simultaneously, the introduction of phaCBA into the acetoin-producing strain BS03 addressed the issue of insufficient intracellular cofactors in the fermentation strain, resulting in the successful production of 70.14 g/L of acetoin through fed-batch fermentation. This study enhances our understanding of Bacillus's cellular response to acetoin-induced stress and provides valuable insights for the development of acetoin-resistant Bacillus strains.


Assuntos
Acetoína , Bacillus subtilis , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Acetoína/metabolismo , Ácido Glutâmico/metabolismo , Fermentação , Perfilação da Expressão Gênica , Arginina , Proteínas de Transporte/genética , Prolina/metabolismo
9.
Phys Chem Chem Phys ; 26(35): 23288-23296, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39196642

RESUMO

Based on first-principles calculations, we predict a new family of chromium-based compounds, ACrTe (A = Na, K, Rb, Cs), which share the same structure as the iron-based superconductor LiFeAs. We show that all these materials are narrow-gap antiferromagnetic (AFM) semiconductors. The AFM order is of the checkerboard type within Cr layers, while the interlayer coupling changes from ferromagnetic (FM) for NaCrTe to AFM for KCrTe, RbCrTe and CsCrTe. Interestingly, we find that the small gap is sensitive to in-plane biaxial strain and magnetic fields, which can tune the bulk compounds to become Dirac and Weyl semimetals and tune the monolayer case to exhibit quantum spin and anomalous Hall effects. Significantly, both Dirac and Weyl semimetals show clean topological structures with a long-sought single pair of Dirac and Weyl points at the Fermi level. Our studies may provide an ideal candidate material to study Dirac and Weyl physics and to realize clean quantum spin and anomalous Hall effects.

10.
Cereb Cortex ; 33(11): 6559-6572, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-36708018

RESUMO

This study aimed to investigate how the ways leaders arise (appointed vs. emergent) affect the leader-follower interaction during creative group communication. Hyperscanning technique was adopted to reveal the underlying interpersonal neural correlates using functional near-infrared spectroscopy. Participants were assigned into 3-person groups to complete a creative problem-solving task. These groups were randomly split into conditions of appointed (condition A) and emergent (condition E) leaders. Creative group outcomes were better in condition E, accompanied by more frequent perspective-taking behaviors between leaders and followers. The interpersonal brain synchronization (IBS) increment for leader-follower pairs was significantly higher at the right angular gyrus (rAG), between the rAG and the right supramarginal gyrus (rSMG), and between the right middle temporal gyrus and the right motor cortex in condition E and positively correlated with perspective-taking behaviors between leaders and followers. The graph-based analysis showed higher nodal betweenness of the rAG and the rSMG in condition E. These results indicated the neural coupling of brain regions involved in mentalizing, semantic processing and motor imagery may underlie the dynamic information transmission between leaders and followers during creative group communication.


Assuntos
Encéfalo , Relações Interpessoais , Humanos , Mapeamento Encefálico/métodos , Tálamo , Comunicação
11.
Cereb Cortex ; 33(5): 1630-1642, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35441220

RESUMO

This hyperscanning study aimed to identify a neural coupling profile that distinguishes high-creative group dynamics through functional near infrared spectroscopy. A total of 123 dyads completed one creativity task (alternative uses task, AUT) and contrast task (objective characteristics task). A K-means clustering analysis on AUT performance grouped 31/29 dyads into high/low-creative group, respectively. In comparison with the low-creative group, the high-creative group showed: (i) higher collective flexibility and delayed perspective-taking behaviors, but lower immediate perspective-taking behaviors; (ii) enhanced interpersonal brain synchronization (IBS) between the left inferior frontal gyrus (lIFG) and right motor cortex, and nodal Eloc at the right superior temporal gyrus (rSTG); (iii) declined intrapersonal functional connectivity between the right angular gyrus (rAG) and rSTG, and IBS between the lIFG and rAG. The enhanced neural couplings positively correlated with group creative performance, whereas a reverse correlation pattern existed in the declined ones. A leave-one-out cross-validation analysis showed these neural couplings reliably predicted group creative performance within the sample. These indicate that high-creative group dynamics are characterized by utilizing partners' shared information when necessary (e.g. encountering idea exhaustion). A neural coupling profile consisting of sophisticated interplays between regions within frontal, temporal, and parietal lobes may underlie high-creative creative dynamics.


Assuntos
Mapeamento Encefálico , Humanos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Criatividade , Dinâmica de Grupo , Córtex Pré-Frontal
12.
Cogn Emot ; : 1-22, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160645

RESUMO

A substantial body of empirical research has focused on the interaction between creativity and mood, yet the results regarding the impact of anger on creative performance are notably varied. To clarify the overall relationship between the two, a three-level meta-analysis employing a random effects model was conducted. This analysis reviewed 115 effect sizes from 2,413 participants, revealing that anger is significantly positively correlated with creative performance (r = 0.184, 95% CI [0.111, 0.254]). The strength of this correlation was found to be moderated by the general and malevolent facets of creativity, as well as the procedures used for mood induction. Specifically, anger appears to enhance creative performance, particularly when it is elicited through imaginative processes and directed towards malevolent facet of creativity. However, the link between anger and creative performance was not influenced by the type of creative task used, the reported creative outcome, or the time limitation of the task. These findings contribute to refining the theoretical frameworks of mood and creativity and highlight the practical implications of utilising anger to moderate creative performance.

13.
Zhongguo Zhong Yao Za Zhi ; 49(17): 4672-4686, 2024 Sep.
Artigo em Zh | MEDLINE | ID: mdl-39307805

RESUMO

The main chemical components of Yangxue Qingnao Wan(YXQNW) were analyzed and identified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS). According to the mass spectrometry information, Mass Hunter 10.0 analysis software was used to compare the collected quasi-molecular ion peaks and secondary fragment ions with literature and reference substances. A total of 131 compounds were identified from YXQNW, including 11 phenylpropanoids, 11 flavonoids, 42 nitrogen-containing compounds, 12 terpenoids, 17 phthalides, 23 quinones, and 15 other compounds. The anti-aging activity of YXQNW and six compounds from YXQNW, including rosmarinic acid, gallic acid, rutin, umbelliferone, hyperoside, and vanillic acid, were evaluated by D-galactose(D-gal)-induced HT22 cell senescence model. The effects of the compounds on HT22 cell damage and individual cell proliferation ability were observed from overall and individual perspectives by the Beyo Click~(TM) EdU-555 cell proliferation kit, and apoptosis was detected by the Annexin V-FITC/PI double staining apoptosis detection kit. Finally, the anti-aging effect of the compounds was tested by a cell senescence ß-galactosidase staining kit. This study provides a more comprehensive analysis of the chemical components of YXQNW and evaluates its anti-aging effect, which will provide a scientific basis for basic research on the efficacy of YXQNW for the treatment of various neurological diseases, such as Alzheimer's disease(AD), headache, and memory loss.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Camundongos , Linhagem Celular , Envelhecimento/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Humanos
14.
Nucleic Acids Res ; 49(1): 114-126, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33290558

RESUMO

Histone modifications and their functional readout serve as an important mechanism for gene regulation. Lysine benzoylation (Kbz) on histones is a recently identified acylation mark associated with active transcription. However, it remains to be explored whether putative readers exist to recognize this epigenetic mark. Here, our systematic binding studies demonstrated that the DPF and YEATS, but not the Bromodomain family members, are readers for histone Kbz. Co-crystal structural analyses revealed a 'hydrophobic encapsulation' and a 'tip-sensor' mechanism for Kbz readout by DPF and YEATS, respectively. Moreover, the DPF and YEATS family members display subtle yet unique features to create somewhat flexible engagements of different acylation marks. For instance, YEATS2 but not the other YEATS proteins exhibits best preference for Kbz than lysine acetylation and crotonylation due to its wider 'tip-sensor' pocket. The levels of histone benzoylation in cultured cells or in mice are upregulated upon sodium benzoate treatment, highlighting its dynamic regulation. In summary, our work identifies the first readers for histone Kbz and reveals the molecular basis underlying Kbz recognition, thus paving the way for further functional dissections of histone benzoylation.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epigenômica , Código das Histonas , Família Multigênica , Benzoato de Sódio/farmacologia , Fatores de Transcrição/metabolismo , Acilação , Sequência de Aminoácidos , Animais , Linhagem Celular , Proteínas Cromossômicas não Histona/química , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina/química , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Fatores de Transcrição/química
15.
Ecotoxicol Environ Saf ; 255: 114806, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36948010

RESUMO

Cancer, the second largest human disease, has become a major public health problem. The prediction of chemicals' carcinogenicity before their synthesis is crucial. In this paper, seven machine learning algorithms (i.e., Random Forest (RF), Logistic Regression (LR), Support Vector Machines (SVM), Complement Naive Bayes (CNB), K-Nearest Neighbor (KNN), XGBoost, and Multilayer Perceptron (MLP)) were used to construct the carcinogenicity triple classification prediction (TCP) model (i.e., 1A, 1B, Category 2). A total of 1444 descriptors of 118 hazardous organic chemicals were calculated by Discovery Studio 2020, Sybyl X-2.0 and PaDEL-Descriptor software. The constructed carcinogenicity TCP model was evaluated through five model evaluation indicators (i.e., Accuracy, Precision, Recall, F1 Score and AUC). The model evaluation results show that Accuracy, Precision, Recall, F1 Score and AUC evaluation indicators meet requirements (greater than 0.6). The accuracy of RF, LR, XGBoost, and MLP models for predicting carcinogenicity of Category 2 is 91.67%, 79.17%, 100%, and 100%, respectively. In addition, the constructed machine learning model in this study has potential for error correction. Taking XGBoost model as an example, the predicted carcinogenicity level of 1,2,3-Trichloropropane (96-18-4) is Category 2, but the actual carcinogenicity level is 1B. But the difference between Category 2 and 1B is only 0.004, indicating that the XGBoost is one optimum model of the seven constructed machine learning models. Besides, results showed that functional groups like chlorine and benzene ring might influence the prediction of carcinogenic classification. Therefore, considering functional group characteristics of chemicals before constructing the carcinogenicity prediction model of organic chemicals is recommended. The predicted carcinogenicity of the organic chemicals using the optimum machine leaning model (i.e., XGBoost) was also evaluated and verified by the toxicokinetics. The RF and XGBoost TCP models constructed in this paper can be used for carcinogenicity detection before synthesizing new organic substances. It also provides technical support for the subsequent management of organic chemicals.


Assuntos
Carcinógenos , Substâncias Perigosas , Aprendizado de Máquina , Compostos Orgânicos , Teorema de Bayes , Carcinogênese , Carcinógenos/toxicidade , Carcinógenos/química , Substâncias Perigosas/química , Substâncias Perigosas/toxicidade , Compostos Orgânicos/toxicidade , Compostos Orgânicos/química , Máquina de Vetores de Suporte , Organização Mundial da Saúde , Algoritmos , Estados Unidos , União Europeia , China , Bases de Dados Factuais
16.
Nano Lett ; 22(13): 5544-5552, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35699945

RESUMO

In situ monitoring of the evolution of intermediates and catalysts during hydrogen oxidation reaction (HOR) processes and elucidating the reaction mechanism are crucial in catalysis and energy science. However, spectroscopic information on trace intermediates on catalyst surfaces is challenging to obtain due to the complexity of interfacial environments and lack of in situ techniques. Herein, core-shell nanoparticle-enhanced Raman spectroscopy was employed to probe alkaline HOR processes on representative PtRu surfaces. Direct spectroscopic evidence of an OHad intermediate and RuOx (Ru(+3)/Ru(+4)) surface oxides is simultaneously obtained, verifying that Ru doping onto Pt promotes OHad adsorption on the RuOx surface to react with Had adsorption on the Pt surface to form H2O. In situ Raman, XPS, and DFT results reveal that RuOx coverage tunes the electronic structure of PtRuOx to optimize the adsorption energy of OHad on catalyst surfaces, leading to an improvement in HOR activity. Our findings provide mechanistic guidelines for the rational design of HOR catalysts with high activity.

17.
J Environ Manage ; 345: 118898, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37657295

RESUMO

The biodegradation treatment of dioxins has long been of interest due to its good ecological and economic effects. In this study, the biodegradability of polychlorinated dibenzo-p-dioxins (PCDDs) were investigated by constructing machine learning and multiple linear regression models. The maximum chlorine atomic charge (qHirshfeldCl+), which characterizes the biodegradation ability of PCDDs, was used as the response value. The random forest model was used to rank the importance on the 1471 descriptors of PCDDs, and the BCUTp-1 h, QXZ, JGI4, ATSC8c, VE3_Dt, topoShape, and maxwHBa were screened as the important descriptors by Pearson's correlation coefficient method. A quantitative structure-activity relationship (QSAR) model was constructed to predict the biodegradability of PCDDs. In addition, the extreme gradient boosting (XGBoost) and random forest model were also constructed and proved the good predictability of QSAR model. The biodegradability of polychlorinated dibenzofurans (PCDFs) can also be predicted by the constructed three models from a certain level after adjusting some model parameters, which further proved the versatility of the models. Besides, the sensitivity analysis of the QSAR model and a 3D-QSAR model was developed to investigate the biodegradability mechanisms of PCDDs. Results showed that the descriptors BCUTp-1 h, JGI4, and maxwHBa were the key descriptors in the biodegradability effect by the sensitivity analysis of the QSAR model. Coupled with the results of PCDDs biodegradability 3D-QSAR model, BCUTp-1 h, JGI4, and maxwHBa were confirmed as the main descriptors that affect the biodegradability of dioxins. This study provides a novel theoretical perspective for the research of the biodegradation of both PCDDs and PCDFs dioxins.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Biodegradação Ambiental , Cloretos , Cloro , Dibenzofuranos Policlorados
18.
Neuroimage ; 261: 119515, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35932994

RESUMO

Non-verbal cues tone our communication. Previous studies found that non-verbal factors, such as spatial distance and gaze direction, significantly impact interpersonal communication. However, little is known about the behind multi-brain neural correlates and whether it could affect high-level creative group communication. Here, we provided a new, scalable, and neuro-based approach to explore the effects of non-verbal factors on different communication tasks, and revealed the underlying multi-brain neural correlates using fNIRS-based hyperscanning technique. Across two experiments, we found that closer spatial distance and more direct gaze angle could promote collaborative behaviors, improve both creative and non-creative communication outcomes, and enhance inter-brain neural synchronization. Moreover, compared to the non-creative communication task, participants' inter-brain network was more intertwined when performing the creative communication task. These findings suggest that close spatial distance and direct gaze serve as positive social cues, bringing interacting brains into alignment and optimizing inter-brain information transfer, thus improving communication outcomes.


Assuntos
Mapeamento Encefálico , Relações Interpessoais , Encéfalo , Mapeamento Encefálico/métodos , Comunicação , Humanos , Redes Neurais de Computação
19.
Phys Rev Lett ; 128(1): 016402, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061489

RESUMO

A recent experiment reported the evidence of dispersing one-dimensional Majorana mode trapped by the crystalline domain walls in FeSe_{0.45}Te_{0.55}. Here, we perform the first-principles calculations to show that iron atoms in the domain wall spontaneously form the ferromagnetic order in line with orientation of the wall. The ferromagnetism can impose a π phase difference between the domain-wall-separated surface superconducting regimes under the appropriate width and magnetization of the wall. Accordingly, the topological surface superconducting state of FeSe_{0.45}Te_{0.55} can give rise to one-dimensional Majorana modes trapped by the wall. More interestingly, we further propose a surface junction in the form of FeSe_{0.45}Te_{0.55}-ferromagnet-FeSe_{0.45}Te_{0.55}, which can be adopted to create and fuse the Majorana zero modes through controlling the width or magnetization of the interior ferromagnetic barrier. The braiding and readout of Majorana zero modes can be realized by the designed device. Such surface junction has the potential application in the superconducting topological quantum computation.

20.
Phys Chem Chem Phys ; 24(13): 7893-7900, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35302567

RESUMO

Based on first-principles calculations, we predict five global stable molybdenum phosphorus compounds in the pressure range of 0-300 GPa. All of them display superconductivity with different transition temperatures. Meanwhile, we find that a metastable crystal hex-MoP2, crystallized in a noncentrosymmetric structure, is a double-Weyl semimetal and the Weyl point is in the H-K path. The long Fermi arcs and the topological surface states, which can be observed by angle-resolved photoemission spectroscopy, emerge at the (100) surface below the Fermi level. Furthermore, we find that the superconductivity in hex-MoP2 can be enhanced by carrier doping. Due to the breaking of inversion symmetry, the unconventional spin-triplet pairing coexists with spin-singlet pairing in channel . Based on our theoretical model, there are the superconducting band gaps in both pairings. Our work provides a new platform of hex-MoP2 for studying both topological double-Weyl semimetal and superconductivity.

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