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Nucleic acid ADP-ribosylation has been established as a novel modification found in a wide diversity of prokaryotic and eukaryotic organisms. tRNA 2'-phosphotransferase 1 (TRPT1/TPT1/KptA) possesses ADP-ribosyltransferase (ART) activity and is able to ADP-ribosylate nucleic acids. However, the underlying molecular mechanism remains elusive. Here, we determined crystal structures of TRPT1s in complex with NAD+ from Homo sapiens, Mus musculus and Saccharomyces cerevisiae. Our results revealed that the eukaryotic TRPT1s adopt common mechanisms for both NAD+ and nucleic acid substrate binding. The conserved SGR motif induces a significant conformational change in the donor loop upon NAD+ binding to facilitate the catalytic reaction of ART. Moreover, the nucleic acid-binding residue redundancy provides structural flexibility to accommodate different nucleic acid substrates. Mutational assays revealed that TRPT1s employ different catalytic and nucleic acid-binding residues to perform nucleic acid ADP-ribosylation and RNA 2'-phosphotransferase activities. Finally, cellular assays revealed that the mammalian TRPT1 is able to promote endocervical HeLa cell survival and proliferation. Together, our results provide structural and biochemical insights into the molecular mechanism of TRPT1 for nucleic acid ADP-ribosylation.
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Fosfotransferasas (Aceptor de Grupo Alcohol) , Proteínas de Saccharomyces cerevisiae , Animales , Humanos , Ratones , Adenosina Difosfato Ribosa/metabolismo , ADP Ribosa Transferasas/genética , ADP Ribosa Transferasas/metabolismo , ADP-Ribosilación , Células HeLa , NAD/metabolismo , Ácidos Nucleicos/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genéticaRESUMEN
Salt stress is one of the major causes of reduced crop production, limiting agricultural development globally. Plants have evolved with complex systems to maintain the balance between growth and stress responses, where signaling pathways such as hormone signaling play key roles. Recent studies revealed that hormones are modulated by microRNAs (miRNAs). Previously, two sweet sorghum (Sorghum bicolor) inbred lines with different salt tolerance were identified: the salt-tolerant M-81E and the salt-sensitive Roma. The levels of endogenous hormones in M-81E and Roma varied differently under salt stress, showing a different balance between growth and stress responses. miRNA and degradome sequencing showed that the expression of many upstream transcription factors regulating signal transduction and hormone-responsive genes was directly induced by differentially expressed miRNAs, whose levels were very different between the two sweet sorghum lines. Furthermore, the effects of representative miRNAs on salt tolerance in sorghum were verified through a transformation system mediated by Agrobacterium rhizogenes. Also, miR-6225-5p reduced the level of Ca2+ in the miR-6225-5p-overexpressing line by inhibiting the expression of the Ca2+ uptake gene SbGLR3.1 in the root epidermis and affected salt tolerance in sorghum. This study provides evidence for miRNA-mediated growth and stress responses in sweet sorghum.
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MicroARNs , Sorghum , MicroARNs/genética , MicroARNs/metabolismo , Sorghum/metabolismo , Estrés Fisiológico/genética , Estrés Salino/genética , Grano Comestible/genética , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas/genéticaRESUMEN
BACKGROUND: Tertiary lymphoid structures (TLSs) are potential prognostic indicators. Radiomics may help reduce unnecessary invasive operations. PURPOSE: To analyze the association between TLSs and prognosis, and to establish a nomogram model to evaluate the expression of TLSs in breast cancer (BC) patients. STUDY TYPE: Retrospective. POPULATION: Two hundred forty-two patients with localized primary BC (confirmed by surgery) were divided into BC + TLS group (N = 122) and BC - TLS group (N = 120). FIELD STRENGTH/SEQUENCE: 3.0T; Caipirinha-Dixon-TWIST-volume interpolated breath-hold sequence for dynamic contrast-enhanced (DCE) MRI and inversion-recovery turbo spin echo sequence for T2-weighted imaging (T2WI). ASSESSMENT: Three models for differentiating BC + TLS and BC - TLS were developed: 1) a clinical model, 2) a radiomics signature model, and 3) a combined clinical and radiomics (nomogram) model. The overall survival (OS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) were compared to evaluate the prognostic value of TLSs. STATISTICAL TESTS: LASSO algorithm and ANOVA were used to select highly correlated features. Clinical relevant variables were identified by multivariable logistic regression. Model performance was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC), and through decision curve analysis (DCA). The Kaplan-Meier method was used to calculate the survival rate. RESULTS: The radiomics signature model (training: AUC 0.766; test: AUC 0.749) and the nomogram model (training: AUC 0.820; test: AUC 0.749) showed better validation performance than the clinical model. DCA showed that the nomogram model had a higher net benefit than the other models. The median follow-up time was 52 months. While there was no significant difference in 3-year OS (P = 0.22) between BC + TLS and BC - TLS patients, there were significant differences in 3-year DFS and 3-year DMFS between the two groups. DATA CONCLUSION: The nomogram model performs well in distinguishing the presence or absence of TLS. BC + TLS patients had higher long-term disease control rates and better prognoses than those without TLS. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.
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Neoplasias de la Mama , Estructuras Linfoides Terciarias , Humanos , Femenino , Pronóstico , Neoplasias de la Mama/diagnóstico por imagen , Radiómica , Estudios Retrospectivos , Imagen por Resonancia MagnéticaRESUMEN
BACKGROUND AND AIMS: Few studies have focused on the outcomes of Wilson's disease (WD) diagnosed before age of 5 years. This study aimed to summarize the clinical features of early diagnosed WD and analyse treatment outcomes and the risk factors associated with treatment failure. METHODS: A total of 139 children confirmed with WD before 5 years were enrolled in this study. Only patients with follow-up over 1 year were analysed with Kaplan-Meier survival analysis. The composite outcomes included death, progression to liver failure or acute hepatitis, development of renal or neurological symptoms and persistent elevation of alanine aminotransferase (ALT). The treatment failure was defined as occurrence of at least one of above outcomes. RESULTS: Among 139 WD patients at diagnosis, two (1.4%) WD patients presented with symptomatic liver disease, whereas 137 (98.6%) were phenotypically asymptomatic, including 135 with elevated ALT and 2 with normal liver function. Median serum ceruloplasmin (Cp) was 3.1 mg/dL, and urinary copper excretion was 87.4 µg/24-h. There were 71 variants identified in the the copper-transporting ATPase beta gene, and 29 were loss of function (LOF). 51 patients with LOF variant were younger at diagnosis and had lower Cp than 88 patients without LOF. Among 93 patients with over 1 year of follow-up, 19 (20.4%) received zinc monotherapy, and 74 (79.6%) received a zinc/D-penicillamine combination therapy. 14 (15.1%) patients underwent treatment failure, and its occurrence was associated with poor compliance (p < .01). CONCLUSIONS: Cp is a reliable biomarker for early diagnosis, and zinc monotherapy is an effective treatment for WD during early childhood. Good treatment compliance is critical to achieve a favourable outcome.
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BACKGROUND: Prior studies reported that elevated asprosin level was associated with obesity in adults and animal models. However, the relationship between asprosin level and children with obeisty remains controversial. The aim of our analysis was to systematically review available literatures linking asprosin and children with obesity for a comprehensive understanding of the relationship between circulating asprosin level and obesity in children. METHODS: Eight databases were gleaned for studies published up to January 2024. Standard mean difference with 95% confidence interval (CI) and Fisher's Z transformation was calculated to evaluate the relationship between asprosin level and children with obesity using the Review Manager 5.4 Software. Other indicators were measured via mean difference with 95% CI. RESULTS: Six observational studies were included both in systematic review and meta-analysis. The current evidence indicated that no significant difference was observed in the level of circulating asprosin between the children with and without obesity (SMD = 0.37; 95% CI:-0.22-0.95, p = 0.22). However, Fisher's Z transformation suggested the positive association of circulating asprosin levels and clinical index measuring the degree of obesity: total cholesterol (Fisher's Z: 0.11, 95% CI: 0.02-0.20, p = 0.02). CONCLUSIONS: Circulating asprosin level was not independently related to childhood obesity currently. More rigorous longitudinal researches were required to disentangle the causations. However, the positive association of asprosin levels and total cholesterol indicated that asprosin might get involved in the lipid-metabolism of childhood obesity, asprosin might be a prospective bio-index and targeted treatment of total cholesterol metabolism besides the role of glucogenic and orexigenic. TRIAL REGISTRATION: Prospero ID: CRD42023426476.
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Fibrilina-1 , Obesidad Infantil , Adulto , Animales , Niño , Humanos , Colesterol , Fibrilina-1/sangre , Glucosa , Obesidad Infantil/sangre , Estudios ProspectivosRESUMEN
Nanotechnology has contributed important innovations to medicine and dentistry, and has also offered various applications to the field of orthodontics. Intraoral appliances must function in a complex environment that includes digestive enzymes, a diverse microbiome, mechanical stress, and fluctuations of pH and temperature. Nanotechnology can improve the performance of orthodontic brackets and archwires by reducing friction, inhibiting bacterial growth and biofilm formation, optimizing tooth remineralization, improving corrosion resistance and biocompatibility of metal substrates, and accelerating or decelerating orthodontic tooth movement through the application of novel nanocoatings, nanoelectromechanical systems, and nanorobots. This comprehensive review systematically explores the orthodontic applications of nanotechnology, particularly its impacts on tooth movement, antibacterial activity, friction reduction, and corrosion resistance. A search across PubMed, the Web of Science Core Collection, and Google Scholar yielded 261 papers, of which 28 met our inclusion criteria. These selected studies highlight the significant benefits of nanotechnology in orthodontic devices. Recent clinical trials demonstrate that advancements brought by nanotechnology may facilitate the future delivery of more effective and comfortable orthodontic care.
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Antibacterianos , Fricción , Nanotecnología , Ortodoncia , Técnicas de Movimiento Dental , Humanos , Técnicas de Movimiento Dental/instrumentación , Corrosión , Antibacterianos/farmacología , Antibacterianos/químicaRESUMEN
Glycosylation and phosphorylation rank as paramount post-translational modifications, and their analysis heavily relies on enrichment techniques. In this work, a facile approach was developed for the one-step simultaneous enrichment and stepwise elution of glycoproteins and phosphoproteins. The core of this approach was the application of the novel titanium (IV) ion immobilized poly(glycidyl methacrylate) microparticles functionalized with dendrimer polyethylenimine and phytic acid. The microparticles possessed dual enrichment capabilities due to their abundant titanium ions and hydroxyl groups on the surface. They demonstrate rapid adsorption equilibrium (within 30 min) and exceptional adsorption capacity for ß-casein (1107.7 mg/g) and horseradish peroxidase (438.6 mg/g), surpassing that of bovine serum albumin (91.7 mg/g). Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was conducted to validate the enrichment capability. Experimental results across various biological samples, including standard protein mixtures, non-fat milk, and human serum, demonstrated the remarkable ability of these microparticles to enrich low-abundance glycoproteins and phosphoproteins from biological samples.
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Dendrímeros , Glicoproteínas , Fosfoproteínas , Polietileneimina , Ácidos Polimetacrílicos , Titanio , Glicoproteínas/química , Fosfoproteínas/química , Polietileneimina/química , Dendrímeros/química , Humanos , Titanio/química , Ácidos Polimetacrílicos/química , Interacciones Hidrofóbicas e Hidrofílicas , Propiedades de Superficie , Animales , Tamaño de la Partícula , Adsorción , BovinosRESUMEN
Context: In China, the dearth of adept rehabilitation nurses has escalated into a pressing concern. Conventional nursing education has stymied nurses' autonomous scholarly pursuits. The case-teaching methodology can augment students' competencies and zeal, culminating in the enrichment of educational excellence. Objective: The study intended to elucidate the principles, taxonomy, and enactment of the case-teaching methodology and examine its salutary impacts on nursing practitioners and educators. Design: The research team performed a narrative review by searching BMJ Best Practice, OVID EBM, NGC et al databases. The search used the keywords 'Rehabilitation nursing', 'nursing', 'case teaching method'. Setting: The study took place at the Rehabilitation Medicine Center at West China Hospital of Sichuan University in Chengdu, China. Results: The current study scrutinizes the assimilation of the case-teaching methodology within the realm of nursing, dissects emerging paradigms in the standardized training of rehabilitation nursing staff, and furnishes precedents for the evolution of training frameworks in the field of rehabilitative care. Conclusions: The case-teaching methodology not only serves as an instructional tool but also embodies a fundamental transformation in the modernization of nursing education, embodying the aspiration for excellence, the desire for continuous improvement, and a dedication to the highest standards of patient care.
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Enfermería en Rehabilitación , Humanos , China , Enfermería en Rehabilitación/educación , Enfermería en Rehabilitación/normas , Educación en Enfermería/métodos , Educación en Enfermería/normas , Competencia Clínica/normasRESUMEN
Neuropeptides are endogenous active substances within the central and peripheral nervous systems that play important roles in a wide range of brain functions, including metabolism, food intake, social behavior, reproduction, learning, sleep, and wakefulness. This article reviews recent advances in the involvement of neuropeptides in vascular dementia. Neuropeptides are present in the brain as chemical signals and last for nearly 50 years. Peptide hormones are chemical signals of the endocrine system. Thus, neuropeptides are the most diverse class of signaling molecules in the brain, involving the genomes of many mammals, encoding neuropeptide precursors and many bioactive neuropeptides. Here the aim is to describe the recent advances in classical neuropeptides, as well as putative neuropeptides from other families, in the control of or as diagnostic tools for vascular dementia. Additionally, its molecular mechanisms are described to explore new avenues of treatment and early diagnosis, as there is increasing evidence that dysregulation of vascular processes is associated with different pathological conditions.
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Demencia Vascular , Neuropéptidos , Animales , Humanos , Demencia Vascular/diagnóstico , Neuropéptidos/metabolismo , Encéfalo/metabolismo , Transducción de Señal , Biomarcadores/metabolismo , Mamíferos/metabolismoRESUMEN
Kidney stones, represented by the calcium oxalate (CaOx) type, are highly prevalent and recrudescent. Cumulative evidence shows regular consumption of lemonade intervenes with stone development. However, the detailed mechanism remains obscure. Here, extracellular vesicle-like nanoparticles (LEVNs) isolated from lemonade are demonstrated to traffick from the gut to the kidney, primarily enriched in tubule cells. Oral administration of LEVNs significantly alleviates the progression of kidney stones in rats. Mechanistically, in addition to altering the crystallization of CaOx toward a less stable subtype, LEVNs suppress the CaOx-induced endoplasmic reticulum stress response of tubule cells, as indicated by homeostasis of specific signaling molecules and restoration of subcellular function, thus indirectly inhibiting stone formation. To exercise this regulation, endocytosed LEVNs traffick along the microtubules throughout the cytoplasm and are eventually recruited into lysosomes. In conclusion, this study reveals a LEVNs-mediated mechanism against renal calculi and provides positive evidence for consumption of lemonade preventing stone formation.
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Vesículas Extracelulares , Cálculos Renales , Nanopartículas , Ratas , Animales , Oxalato de Calcio/química , Riñón , Cálculos Renales/tratamiento farmacológico , Cálculos Renales/química , Estrés del Retículo EndoplásmicoRESUMEN
Transition-metal-oxide@heteroatom doped porous carbon composites have attracted considerable research interest because of their large theoretical adsorption capacity, excellent electrical conductivity and well-developed pore structure. Herein, Mn3O4-loaded phosphorus-doped porous carbon composites (Mn3O4@PC-900) were designed and fabricated for the electrosorption of La3+ in aqueous solutions. Due to the synergistic effect between Mn3O4 and PC-900, and the active sites provided by Mn-O-Mn, C/PO, C-P-O and Mn-OH, Mn3O4@PC-900 exhibits high electrosorption performance. The electrosorption value of Mn3O4@PC-900 was 45.34% higher than that of PC-900, reaching 93.02 mg g-1. Moreover, the adsorption selectivity reached 87.93% and 89.27% in La3+/Ca2+ and La3+/Na+ coexistence system, respectively. After 15 adsorption-desorption cycles, its adsorption capacity and retention rate were 50.34 mg g-1 and 54.12%, respectively. The electrosorption process is that La3+ first accesses the pores of Mn3O4@PC-900 to generate an electric double layer (EDL), and then undergoes further Faradaic reaction with Mn3O4 and phosphorus-containing functional groups through intercalation, surface adsorption and complexation. This work is hoped to offer a new idea for exploring transition-metal-oxide @ heteroatom doped porous carbon composites for separation and recovery of rare earth elements (REEs) by capacitive deionization.
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Carbono , Electrodos , Lantano , Fósforo , Lantano/química , Fósforo/química , Carbono/química , Adsorción , Porosidad , Óxidos/química , Iones , Compuestos de Manganeso/químicaRESUMEN
Objective To evaluate the value of SOX1 and PAX1 gene methylation detection in the secondary triage of high-grade cervical lesions.Methods Exfoliated cervical cells were collected from 122 patients tested positive for human papilloma virus (HPV) and subjected to thin-prep cytologic test (TCT) and SOX1/PAX1 gene methylation tests.Results The HPV test combined with TCT showed the sensitivity of 95.24% and the specificity of 23.75% for detecting cervical intraepithelial neoplasia (CIN) grade 2 and above (CIN2+).After the addition of the SOX1/PAX1 gene methylation detection in secondary triage,the sensitivity for detecting CIN2+ was 83.33%,which had no statistically significant difference from the sensitivity of TCT combined with HPV test (P=0.078).However,the specificity reached 77.50%,which was significantly higher than that of HPV test combined with TCT (P<0.001).The SOX1/PAX1 gene methylation level in the CIN2+ group was higher than those in the normal cervical tissue and the CIN1 group(P<0.001).The cut-off values of SOX1 and PAX1 gene methylation for CIN2+ detection were -11.81 and -11.98,respectively.Conclusion Adding the detection of SOX1/PAX1 gene methylation in secondary triage significantly improves the efficiency and accuracy of CIN2+ detection.
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Metilación de ADN , Factores de Transcripción Paired Box , Factores de Transcripción SOXB1 , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Humanos , Femenino , Factores de Transcripción Paired Box/genética , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/virología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/virología , Factores de Transcripción SOXB1/genética , Adulto , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenRESUMEN
Target identification by modification-free proteomic approaches can potentially reveal the pharmacological mechanism of small molecular compounds. By combining the recent solvent-induced protein precipitation (SIP) method with TMT-labeling quantitative proteomics, we propose solvent-induced proteome profiling (SIPP) approach to identify small molecule-protein interactions. The SIPP approach enables to depict denaturation curves of the target protein by varying concentrations of organic solvents to induce unfolding and precipitation of the cellular proteome. By using this approach, we have successfully identified the known targets of market drugs and natural products and extended the proteome information of SIP for target identification.
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Proteoma , Proteómica , Solventes , Espectrometría de MasasRESUMEN
Salt stress adversely affects plant growth and development. It is necessary to understand the underlying salt response mechanism to improve salt tolerance in plants. MYB transcription factors can regulate plant responses to salt stress. However, only a few studies have explored the role of MYB TFs in Sorghum bicolor (L.) Moench. So we decided to make a systematic analysis and research on the sorghum MYB family. A total of 210 MYB genes in sorghum were identified in this study. Furthermore, 210 MYB genes were distributed across ten chromosomes, named SbMYB1-SbMYB210. To study the phylogeny of the identified TFs, 210 MYB genes were divided into six subfamilies. We further demonstrated that SbMYB genes have evolved under strong purifying selection. SbMYBAS1 (SbMYB119) was chosen as the study object, which the expression decreased under salt stress conditions. Further study of the SbMYBAS1 showed that SbMYBAS1 is located in the nucleus. Under salt stress conditions, Arabidopsis plants overexpressed SbMYBAS1 showed significantly lower dry/fresh weight and chlorophyll content but significantly higher membrane permeability, MDA content, and Na+/K+ ratio than the wild-type Arabidopsis plants. Yeast two-hybrid screening result showed that SbMYBAS1 might interact with proteins encoded by SORBI_302G184600, SORBI_3009G247900 and SORBI_3004G59600. Results also showed that SbMYBAS1 could regulate the expression of AtGSTU17, AtGSTU16, AtP5CS2, AtUGT88A1, AtUGT85A2, AtOPR2 and AtPCR2 under salt stress conditions. This work laid a foundation for the study of the response mechanism of sorghum MYB gene family to salt stress.
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Arabidopsis , Sorghum , Sorghum/genética , Sorghum/metabolismo , Arabidopsis/genética , Genes myb , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Salino/genética , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , FilogeniaRESUMEN
Salinity is a major factor limiting rice productivity, and developing salt-tolerant (ST) varieties is the most efficient approach. Seventy-eight ST introgression lines (ILs), including nine promising lines with improved ST and yield potential (YP), were developed from four BC2F4 populations from inter-subspecific crosses between an elite Geng (japonica) recipient and four Xian (indica) donors at the Institute of Crop Sciences, Chinese Academy of Agricultural Sciences. Genome-wide characterization of donor introgression identified 35 ST QTLs, 25 of which harbor 38 cloned ST genes as the most likely QTL candidates. Thirty-four are Xian-Geng differentiated ones with the donor (Xian) alleles associated with ST, suggesting differentiated responses to salt stress were one of the major phenotypic differences between the two subspecies. At least eight ST QTLs and many others affecting yield traits were identified under salt/non-stress conditions. Our results indicated that the Xian gene pool contains rich 'hidden' genetic variation for developing superior Geng varieties with improved ST and YP, which could be efficiently exploited by selective introgression. The developed ST ILs and their genetic information on the donor alleles for ST and yield traits would provide a useful platform for developing superior ST and high-yield Geng varieties through breeding by design in the future.
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On account of high capacity and high voltage resulting from anionic redox, Li-rich layered oxides (LLOs) have become the most promising cathode candidate for the next-generation high-energy-density lithium-ion batteries (LIBs). Unfortunately, the participation of oxygen anion in charge compensation causes lattice oxygen evolution and accompanying structural degradation, voltage decay, capacity attenuation, low initial columbic efficiency, poor kinetics, and other problems. To resolve these challenges, a rational structural design strategy from surface to bulk by a facile pretreatment method for LLOs is provided to stabilize oxygen redox. On the surface, an integrated structure is constructed to suppress oxygen release, electrolyte attack, and consequent transition metals dissolution, accelerate lithium ions transport on the cathode-electrolyte interface, and alleviate the undesired phase transformation. While in the bulk, B doping into Li and Mn layer tetrahedron is introduced to increase the formation energy of O vacancy and decrease the lithium ions immigration barrier energy, bringing about the high stability of surrounding lattice oxygen and outstanding ions transport ability. Benefiting from the specific structure, the designed material with the enhanced structural integrity and stabilized anionic redox performs an excellent electrochemical performance and fast-charging property..
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Fe-based mixed phosphate cathodes for Na-ion batteries usually possess weak rate capacity and cycle stability challenges resulting from sluggish diffusion kinetics and poor conductivity under the relatively low preparation temperature. Here, the excellent sodium storage capability of this system is obtained by introducing the high-entropy doping to enhance the electronic and ionic conductivity. As designed high-entropy doping Na4 Fe2.85 (Ni,Co,Mn,Cu,Mg)0.03 (PO4 )2 P2 O7 (NFPP-HE) cathode can release 122 mAh g-1 at 0.1 C, even 85 mAh g-1 at ultrahigh rate of 50 C, and keep a high retention of 82.3% after 1500 cycles at 10 C. Besides, the cathode also exhibits outstanding fast charge capacity in terms of the cyclability and capacity with 105 mAh g-1 at 5 C/1 C, corresponding 94.3% retention after 500 cycles. The combination of in situ X-ray diffraction, density functional theory, conductive-atomic force microscopy, and galvanostatic intermittent titration technique tests reveal that the reversible structure evolution with optimized Na+ migration path and energy barrier boost the Na+ kinetics and improve the interfacial electronic transfer, thus improving performance.
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Step-scheme (S-scheme) heterojunctions have been extensively studied in photocatalytic carbon dioxide (CO2 ) reduction due to their excellent charge separation and high redox ability. The built-in electric field at the interface of a S-scheme heterojunction serves as the driving force for charge transfer, however, the poor interfacial contact greatly restricts the carrier migration rate. Herein, we synthesized the g-C3 N4 /Bi19 Br3 S27 S-scheme heterostructure through inâ situ deposition of Bi19 Br3 S27 (BBS) on porous g-C3 N4 (P-CN) nanosheets. The C-S bonds formed at the interface help to enhance the built-in electric field, thereby promoting the charge transfer and separation. As a result, the CO2 reduction reaction performance of 10 %Bi19 Br3 S27 /g-C3 N4 (BBS/P-CN) reaches 32.78â µmol g-1 h-1 , which is 341.4 and 18.7 times higher than that of pure BBS and P-CN, respectively. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) prove the presence of chemical bonds (C-S) between the P-CN and BBS. The S-scheme charge-transfer mechanism was analyzed via XPS and density functional theory (DFT) calculations. This work provides a new idea for designing heterojunction photocatalysts with interfacial chemical bonds to achieve high charge-transfer and catalytic activity.
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Manipulating the interfacial/surface structure of ligand-stabilized atomically precise metal nanoclusters (NCs) is one of the central tasks in nanoscience because surface motifs are directly related to key properties of nanomaterials. Although great progress has been made in engineering the surface of gold and silver nanoclusters, parallel studies on lighter copper analogues hitherto remain unexplored. In this work, we report the design, synthesis, and structure of a new class of copper nanoclusters featuring virtually identical kernels but different surface motifs. The four Cu29 nanoclusters share the same Cu13 kernel with unprecedented anticuboctahedral architecture. Finely modulating synthetic parameters endows the Cu13 core with diverse surface structures, thus affording the Cu29 series with labile surface coatings. More interestingly, the slight surface modification results in distinct optical and catalytic properties of the cluster compounds, highlighting the importance of the surface structure in shaping the behaviors of copper nanomolecules. This work not only exemplifies the efficiency of surface engineering for controlling properties of well-defined copper nanoclusters but also provides a new family of Cu materials with a clear molecular structure and controlled surface motifs that hold great promise in studying structure-property relationships.
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Phosphides have been used in a wide range of applications due to their excellent optical, mechanical, and catalytic properties. Using an effective unbiased structure searching method combined with first-principles calculations, the phase diagram and physical and chemical properties of aluminum phosphides have been determined at high pressures. The results reveal that the unconventional stoichiometries of Al2P, AlP2, and AlP3 remain stable above 66, 91, and 116 GPa, respectively. Interestingly, the analysis of the phonon spectrum suggests that AlP2 with P21 symmetry can be dynamically stable at atmospheric pressure. In addition, the band gap of 1.51 eV at the HSE06 level and the estimated Vickers hardness of â¼10.54 GPa make P21-AlP2 a hard photoelectric material. Moreover, our electronic properties show that AlP3 with Immm symmetry and AlP2 with I4/mmm structure are metallic at high pressures and further electron-phonon coupling calculations indicate Immm-AlP3 and I4/mmm-AlP2 are superconductors with estimated Tc values of 3.9 K at 150 GPa and 10.2 K at 100 GPa, respectively. Our work provides significant inputs toward understanding novel chemical bonding in aluminum phosphides and gives a direction for the experimental synthesis of multifunctional materials at high pressures.