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1.
ChemSusChem ; : e202401516, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39429049

RESUMO

The electro-catalytic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) provides an attractive route to produce 2, 5-furandicarboxylic acid (FDCA) as a substitute for terephthalic acid used in the plastics industry. Herein, we prepared MoNi4 alloy on nickel foam (NF) using a simple hydrothermal method followed by hydrogen reduction. Applied MoNi4/NF as the bifunctional electrodes for the electro-catalytic HMF oxidation reaction (HMFOR) and HER, 98.7% FDCA yield and 97.3% Faraday efficiency (FE) can be achieved even with HMF concentration as high as 200 mM. Notably, no obvious deactivation was observed after ten consecutive cycles. In-situ Raman, XANES and EXAFS results show that the nickel species of MoNi4/NF is first oxidized to Ni3+ species under the applied voltage, and after undergoing the electro-catalytic HMFOR, then reduced to Ni2-δ state (with a valence between 0 and +2) due to the electron-donating effect from Mo. MoNi4/NF with more than one electron transfer between Ni3+ and Ni2-δ during the HMFOR enables it to have excellent electro-catalytic oxidation ability toward HMFOR.

2.
Neurosci Lett ; 841: 137953, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39214331

RESUMO

The behavioral sensitization, characterized by escalated behavioral responses triggered by recurrent exposure to psychostimulants, involves neurobiological mechanisms that are brain-region and cell-type specific. Enduring neuroadaptive changes have been observed in response to methamphetamine (METH) within the orbitofrontal cortex (OFC), the cell-type specific transcriptional alterations in response to METH sensitization remain understudied. In this study, we utilized Single-nucleus RNA-sequencing (snRNA-seq) to profile the gene expression changes in the OFC of a rat METH sensitization model. The analyses of differentially expressed genes (DEGs) unveiled cell-type specific transcriptional reactions associated with METH sensitization, with the most significant alterations documented in microglial cells. Bioinformatic investigations revealed that distinct functional and signaling pathways enriched in microglia-specific DEGs majorly involved in macroautophagy processes and the activation of N-methyl-D-aspartate ionotropic glutamate receptors (NMDAR). To validate the translational relevance of our findings, we analyzed our snRNA-seq data in conjunction with a transcriptomic study of individuals with opioid use disorder (OUD) and a large-scale Genome-Wide Association Studies (GWAS) from multiple externalizing phenotypes related to drug addiction. The validation analysis confirmed the consistent expression changes of key microglial DEGs in human METH addiction. Moreover, the integration with GWAS data revealed associations between addiction risk genes and the DEGs observed in specific cell types, particularly microglia and excitatory neurons. Our study highlights the importance of cell-type specific transcriptional alterations in the OFC in the context of METH sensitization and their potential translational relevance to human drug addiction.


Assuntos
Estimulantes do Sistema Nervoso Central , Metanfetamina , Córtex Pré-Frontal , Ratos Sprague-Dawley , Metanfetamina/farmacologia , Animais , Masculino , Ratos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Microglia/metabolismo , Microglia/efeitos dos fármacos , Análise de Sequência de RNA/métodos
3.
Front Plant Sci ; 15: 1430467, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988640

RESUMO

The switch defective/sucrose non-fermentable (SWI/SNF) multisubunit complex plays an important role in the regulation of gene expression by remodeling chromatin structure. Three SWI/SNF complexes have been identified in Arabidopsis including BAS, SAS, and MAS. Many subunits of these complexes are involved in controlling plant development and stress response. However, the function of these complexes has hardly been studied in other plant species. In this study, we identified the subunits of the SWI/SNF complex in sorghum and analyzed their evolutionary relationships in six grass species. The grass species conserved all the subunits as in Arabidopsis, but gene duplication occurred diversely in different species. Expression pattern analysis in sorghum (Sorghum bicolor) showed that most of the subunit-encoding genes were expressed constitutively, although the expression level was different. Transactivation assays revealed that SbAN3, SbGIF3, and SbSWI3B possessed transactivation activity, which suggests that they may interact with the pre-initiation complex (PIC) to activate transcription. We chose 12 subunits in sorghum to investigate their interaction relationship by yeast two-hybrid assay. We found that these subunits displayed distinct interaction patterns compared to their homologs in Arabidopsis and rice. This suggests that different SWI/SNF complexes may be formed in sorghum to perform chromatin remodeling functions. Through the integrated analysis of MNase-seq and RNA-seq data, we uncovered a positive relationship between gene expression levels and nucleosome phasing. Furthermore, we found differential global nucleosome enrichments between leaves and roots, as well as in response to PEG treatment, suggesting that dynamics of nucleosome occupancy, which is probably mediated by the SWI/SNF complex, may play important roles in sorghum development and stress response.

4.
J Am Chem Soc ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847362

RESUMO

Prussian blue analogue (PBA)/metal-organic frameworks (MOFs) are multifunctional precursors for the synthesis of metal/metal compounds, carbon, and their derived composites (P/MDCs) in chemical, medical, energy, and other applications. P/MDCs combine the advantages of both the high specific surface area of PBA/MOF and the electronic conductivity of metal compound/carbon. Although the calcination under different atmospheres has been extensively studied, the transformation mechanism of PBA/MOF under hydrothermal conditions remains unclear. The qualitative preparation of P/MDCs in hydrothermal conditions remains a challenge. Here, we select PBA to construct a machine-learning model and measure its hydrothermal phase diagram. The architecture-activity relationship of substances among nine parameters was analyzed for the hydrothermal phase transformation of PBA. Excitingly, we established a universal qualitative model to accurately fabricate 31 PBA derivates. Additionally, we performed three-dimensional reconstructed transmission electron microscopy, X-ray absorption fine structure spectroscopy, ultraviolet photoelectron spectroscopy, in situ X-ray powder diffraction, and theoretical calculation to analyze the advantages of hydrothermal derivatives in the oxygen evolution reaction and clarify their reaction mechanisms. We uncover the unified principles of the hydrothermal phase transformation of PBA, and we expect to guide the design for a wide range of composites.

5.
Plant Physiol Biochem ; 211: 108709, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744082

RESUMO

The COMPASS-like complex, responsible for depositing H3K4 methylation, exhibits a conserved composition across yeast, plants, and animals, with functional analysis highlighting its crucial roles in plant development and stress response. In this study, we identified nine genes encoding four subunits of the COMPASS-like complex through homologous search. Phylogenetic analysis revealed the presence of two additional ASH2 genes in the sorghum genome, specifically expressed in endosperms, suggesting the formation of a unique COMPASS-like complex in sorghum endosperms. Y2H and BiFC protein-protein interaction tests demonstrated the interaction between SbRbBP5 and SbASH2A/B/C, while the association between other subunits appeared weak, possibly due to sequence variations in SbWDR5 or synergistic interactions among COMPASS-like complex subunits. The interaction between ATX1 and the C-Terminal Domain (CTD) of Pol II, reported in Arabidopsis, was not detected in sorghum. However, we made the novel discovery of transcriptional activation activity in RbBP5, which is conserved in sorghum, rice, and Arabidopsis, providing valuable insights into the mechanism by which the COMPASS-like complex regulates gene expression in plants.


Assuntos
Filogenia , Proteínas de Plantas , Sorghum , Sorghum/genética , Sorghum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Nat Commun ; 15(1): 2061, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448433

RESUMO

Plants are capable of altering root growth direction to curtail exposure to a saline environment (termed halotropism). The root cap that surrounds root tip meristematic stem cells plays crucial roles in perceiving and responding to environmental stimuli. However, how the root cap mediates root halotropism remains undetermined. Here, we identified a root cap-localized NAC transcription factor, SOMBRERO (SMB), that is required for root halotropism. Its effect on root halotropism is attributable to the establishment of asymmetric auxin distribution in the lateral root cap (LRC) rather than to the alteration of cellular sodium equilibrium or amyloplast statoliths. Furthermore, SMB is essential for basal expression of the auxin influx carrier gene AUX1 in LRC and for auxin redistribution in a spatiotemporally-regulated manner, thereby leading to directional bending of roots away from higher salinity. Our findings uncover an SMB-AUX1-auxin module linking the role of the root cap to the activation of root halotropism.


Assuntos
Arabidopsis , Fatores de Transcrição , Fatores de Transcrição/genética , Arabidopsis/genética , Regulação da Expressão Gênica , Estresse Salino/genética , Ácidos Indolacéticos
7.
ChemSusChem ; 17(10): e202400162, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38556462

RESUMO

It is still a great challenge to reasonably design green, low cost, high activity and good stability catalysts for overall water splitting (OWS). Here, we introduce a novel catalyst with ferric niobate (FeNbO4) in-situ growing in honey-derived porous carbon of high specific surface area, and its catalytic activity is further enhanced by micro-regulation (oxygen vacancy and N-doping). From the experimental results and density functional theory (DFT) calculations, the oxygen vacancy in catalyst FeNbO4-x@NC regulates the local charge density of active site, thus increasing conductivity and optimizing hydrogen/oxygen species adsorption energy. FeNbO4 in-situ grows within N-doping honey-derived porous carbon, which can enhance active specific surface area exposure, strengthen gaseous substances escape rate, and accelerate electrons/ions transfer and electrolytes diffusion. Moreover, in-situ Raman also confirms O-species generation in oxygen evolution reaction (OER). As a result, the catalyst FeNbO4-x@NC shows good electrochemical performance in OER, HER and OWS.

8.
Nat Commun ; 15(1): 1749, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409130

RESUMO

The copper (Cu)-catalyzed electrochemical CO2 reduction provides a route for the synthesis of multicarbon (C2+) products. However, the thermodynamically favorable Cu surface (i.e. Cu(111)) energetically favors single-carbon production, leading to low energy efficiency and low production rates for C2+ products. Here we introduce in situ copper faceting from electrochemical reduction to enable preferential exposure of Cu(100) facets. During the precatalyst evolution, a phosphate ligand slows the reduction of Cu and assists the generation and co-adsorption of CO and hydroxide ions, steering the surface reconstruction to Cu (100). The resulting Cu catalyst enables current densities of > 500 mA cm-2 and Faradaic efficiencies of >83% towards C2+ products from both CO2 reduction and CO reduction. When run at 500 mA cm-2 for 150 hours, the catalyst maintains a 37% full-cell energy efficiency and a 95% single-pass carbon efficiency throughout.

9.
Nucleic Acids Res ; 52(D1): D770-D776, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37930838

RESUMO

Rhinovirus (RV), a prominent causative agent of both upper and lower respiratory diseases, ranks among the most prevalent human respiratory viruses. RV infections are associated with various illnesses, including colds, asthma exacerbations, croup and pneumonia, imposing significant and extended societal burdens. Characterized by a high mutation rate and genomic diversity, RV displays a diverse serological landscape, encompassing a total of 174 serotypes identified to date. Understanding RV genetic diversity is crucial for epidemiological surveillance and investigation of respiratory diseases. This study introduces a comprehensive and high-quality RV data resource, designated RVdb (http://rvdb.mgc.ac.cn), covering 26 909 currently identified RV strains, along with RV-related sequences, 3D protein structures and publications. Furthermore, this resource features a suite of web-based utilities optimized for easy browsing and searching, as well as automatic sequence annotation, multiple sequence alignment (MSA), phylogenetic tree construction, RVdb BLAST and a serotyping pipeline. Equipped with a user-friendly interface and integrated online bioinformatics tools, RVdb provides a convenient and powerful platform on which to analyse the genetic characteristics of RVs. Additionally, RVdb also supports the efforts of virologists and epidemiologists to monitor and trace both existing and emerging RV-related infectious conditions in a public health context.


Assuntos
Asma , Infecções por Enterovirus , Infecções por Picornaviridae , Rhinovirus , Humanos , Genômica , Filogenia , Infecções por Picornaviridae/genética , Rhinovirus/genética
10.
Adv Mater ; 36(11): e2311105, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38085968

RESUMO

Developing commercially viable electrocatalyst lies at the research hotspot of rechargeable Zn-air batteries, but it is still challenging to meet the requirements of energy efficiency and durability in realistic applications. Strategic material design is critical to addressing its drawbacks in terms of sluggish kinetics of oxygen reactions and limited battery lifespan. Herein, a "raisin-bread" architecture is designed for a hybrid catalyst constituting cobalt nitride as the core nanoparticle with thin oxidized coverings, which is further deposited within porous carbon aerogel. Based on synchrotron-based characterizations, this hybrid provides oxygen vacancies and Co-Nx -C sites as the active sites, resulting from a strong coupling between CoOx Ny nanoparticles and 3D conductive carbon scaffolds. Compared to the oxide reference, it performs enhanced stability in harsh electrocatalytic environments, highlighting the benefits of the oxynitride. Furthermore, the 3D conductive scaffolds improve charge/mass transportation and boost durability of these active sites. Density functional theory calculations reveal that the introduced N species into hybrid can synergistically tune the d-band center of cobalt and improve its bifunctional activity. As a result, the obtained air cathode exhibits bifunctional overpotential of 0.65 V and a battery lifetime exceeding 1350 h, which sets a new record for rechargeable Zn-air battery reported so far.

11.
Angew Chem Int Ed Engl ; 62(52): e202314303, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37942727

RESUMO

Transition metal single atom electrocatalysts (SACs) with metal-nitrogen-carbon (M-N-C) configuration show great potential in oxygen evolution reaction (OER), whereby the spin-dependent electrons must be allowed to transfer along reactants (OH- /H2 O, singlet spin state) and products (O2 , triplet spin state). Therefore, it is imperative to modulate the spin configuration in M-N-C to enhance the spin-sensitive OER energetics, which however remains a significant challenge. Herein, we report a local field distortion induced intermediate to low spin transition by introducing a main-group element (Mg) into the Fe-N-C architecture, and decode the underlying origin of the enhanced OER activity. We unveil that, the large ionic radii mismatch between Mg2+ and Fe2+ can cause a FeN4 in-plane square local field deformation, which triggers a favorable spin transition of Fe2+ from intermediate (dxy 2 dxz 2 dyz 1 dz2 1 , 2.96 µB ) to low spin (dxy 2 dxz 2 dyz 2 , 0.95 µB ), and consequently regulate the thermodyna-mics of the elementary step with desired Gibbs free energies. The as-obtained Mg/Fe dual-site catalyst demonstrates a superior OER activity with an overpotential of 224 mV at 10 mA cm-2 and an electrolysis voltage of only 1.542 V at 10 mA cm-2 in the overall water splitting, which outperforms those of the state-of-the-art transition metal SACs.

12.
Sci Adv ; 9(42): eadh4626, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37862412

RESUMO

Attaining substantial areal capacity (>3 mAh/cm2) and extended cycle longevity in all-solid-state lithium metal batteries necessitates the implementation of solid-state electrolytes (SSEs) capable of withstanding elevated critical current densities and capacities. In this study, we report a high-performing vacancy-rich Li9N2Cl3 SSE demonstrating excellent lithium compatibility and atmospheric stability and enabling high-areal capacity, long-lasting all-solid-state lithium metal batteries. The Li9N2Cl3 facilitates efficient lithium-ion transport due to its disordered lattice structure and presence of vacancies. Notably, it resists dendrite formation at 10 mA/cm2 and 10 mAh/cm2 due to its intrinsic lithium metal stability. Furthermore, it exhibits robust dry-air stability. Incorporating this SSE in Ni-rich LiNi0.83Co0.11Mn0.06O2 cathode-based all-solid-state batteries, we achieve substantial cycling stability (90.35% capacity retention over 1500 cycles at 0.5 C) and high areal capacity (4.8 mAh/cm2 in pouch cells). These findings pave the way for lithium metal batteries to meet electric vehicle performance demands.

13.
Environ Sci Technol ; 57(36): 13496-13505, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37638663

RESUMO

Phase transformation of ferrihydrite to more stable Fe (oxyhydr)oxides, catalyzed by iron(II) [Fe(II)], significantly influences the mobility of heavy metals [e.g., chromium (Cr)] associated with ferrihydrite. However, the impact of organic matter (OM) on the behavior of Cr(III) in the Fe(II)-catalyzed transformation of ferrihydrite and the underlying mechanisms are unclear. Here, the Fe(II)-catalyzed transformation of the coprecipitates of Fe(III), Cr(III), or rice straw-derived OM was studied at the nanoscale and molecular levels using Fe and Cr K-edge X-ray absorption spectroscopy and spherical aberration corrected scanning transmission electron microscopy (Cs-STEM). Batch extraction results suggested that the OM counteracted the enhancement of Cr(III) extractability during the Fe(II)-catalyzed transformation. Cs-STEM and XAS analysis suggested that Cr(III) could be incorporated into the goethite formed by Fe(II)-catalyzed ferrihydrite transformation, which, however, was inhibited by the OM. Furthermore, Cs-STEM analysis also provided direct nanoscale level evidence that residual ferrihydrite could re-immobilize the released Cr(III) during the Fe(II)-catalyzed transformation process. These results highlighted that the decreased extractability of Cr(III) mainly resulted from the inhibition of OM on the Fe(II)-catalyzed transformation of ferrihydrite to secondary Fe (oxyhydr)oxides, which facilitates insightful understanding and prediction of the geochemical cycling of Cr in soils with active redox dynamics.


Assuntos
Cromo , Compostos Férricos , Óxidos , Catálise , Compostos Ferrosos
14.
Psychol Health Med ; 28(9): 2501-2511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37314116

RESUMO

This study aims to investigate influencing factors of quality of life (QoL) and depression among COVID-19 survivors during convalescence. A cross-sectional study was conducted in November 2020 in Wuhan, China. Information on social support, physical activity, QoL and depressive symptoms were assessed using self-administered questionnaires. Multivariate linear regression and multivariate logistic regression were used to assess the risk factors of subdomains of QoL (physical component score (PCS) and mental component score (MCS)) and depression, respectively. A total of 151 COVID-19 survivors (68 males) aged 53.21 (SD: 12.70) years participated in the study. Multivariate linear regression showed that age (ß=-0.241), history of chronic disease (ß=-0.4.774), physical activity (ß = 2.47) and social support (ß = 0.147) were significantly associated with PCS, while having a spouse (ß = 9.571), monthly income (ß = 0.043) and social support (ß = 0.337) were significantly associated with MCS. Logistic regression suggested that participants aged 40-60 years (OR = 10.20, 95%CI: 1.41-73.82) or above 60 years (OR = 15.63, 95%CI: 1.87-131.00), with high school or above education (OR = 5.81, 95%CI: 1.24-27.20), with low/moderate physical activity (low, OR = 2.97, 95%CI: 1.14-7.77; moderate, OR = 3.42, 95%CI: 1.07-10.91) and low/medium social support (low, OR = 4.81, 95% CI: 2.02-11.43; medium, OR = 9.70, 95%CI: 1.17-80.10) were more likely to be depressed, while higher monthly income (≥3000 Yuan RMB/month) was associated with lower risk for depression (OR = 0.27, 95%CI: 0.09-0.82). These findings indicate COVID-19 survivors with older age, having chronic conditions, without a spouse, low monthly income, low level of physical activity and social support had significantly increased risks for poor QoL and depression, and more attention should be given to this population.


Assuntos
COVID-19 , Qualidade de Vida , Masculino , Humanos , Depressão/epidemiologia , Convalescença , Estudos Transversais , COVID-19/epidemiologia , Inquéritos e Questionários , Sobreviventes
15.
Nature ; 617(7962): 724-729, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37138081

RESUMO

The carbon dioxide and carbon monoxide electroreduction reactions, when powered using low-carbon electricity, offer pathways to the decarbonization of chemical manufacture1,2. Copper (Cu) is relied on today for carbon-carbon coupling, in which it produces mixtures of more than ten C2+ chemicals3-6: a long-standing challenge lies in achieving selectivity to a single principal C2+ product7-9. Acetate is one such C2 compound on the path to the large but fossil-derived acetic acid market. Here we pursued dispersing a low concentration of Cu atoms in a host metal to favour the stabilization of ketenes10-chemical intermediates that are bound in monodentate fashion to the electrocatalyst. We synthesize Cu-in-Ag dilute (about 1 atomic per cent of Cu) alloy materials that we find to be highly selective for acetate electrosynthesis from CO at high *CO coverage, implemented at 10 atm pressure. Operando X-ray absorption spectroscopy indicates in situ-generated Cu clusters consisting of <4 atoms as active sites. We report a 12:1 ratio, an order of magnitude increase compared to the best previous reports, in the selectivity for acetate relative to all other products observed from the carbon monoxide electroreduction reaction. Combining catalyst design and reactor engineering, we achieve a CO-to-acetate Faradaic efficiency of 91% and report a Faradaic efficiency of 85% with an 820-h operating time. High selectivity benefits energy efficiency and downstream separation across all carbon-based electrochemical transformations, highlighting the importance of maximizing the Faradaic efficiency towards a single C2+ product11.

16.
Nat Commun ; 14(1): 1719, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977716

RESUMO

Improving the dispersion of active sites simultaneous with the efficient harvest of photons is a key priority for photocatalysis. Crystalline silicon is abundant on Earth and has a suitable bandgap. However, silicon-based photocatalysts combined with metal elements has proved challenging due to silicon's rigid crystal structure and high formation energy. Here we report a solid-state chemistry that produces crystalline silicon with well-dispersed Co atoms. Isolated Co sites in silicon are obtained through the in-situ formation of CoSi2 intermediate nanodomains that function as seeds, leading to the production of Co-incorporating silicon nanocrystals at the CoSi2/Si epitaxial interface. As a result, cobalt-on-silicon single-atom catalysts achieve an external quantum efficiency of 10% for CO2-to-syngas conversion, with CO and H2 yields of 4.7 mol g(Co)-1 and 4.4 mol g(Co)-1, respectively. Moreover, the H2/CO ratio is tunable between 0.8 and 2. This photocatalyst also achieves a corresponding turnover number of 2 × 104 for visible-light-driven CO2 reduction over 6 h, which is over ten times higher than previously reported single-atom photocatalysts.

17.
Nat Commun ; 14(1): 146, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627277

RESUMO

High-energy Ni-rich layered oxide cathode materials such as LiNi0.8Mn0.1Co0.1O2 (NMC811) suffer from detrimental side reactions and interfacial structural instability when coupled with sulfide solid-state electrolytes in all-solid-state lithium-based batteries. To circumvent this issue, here we propose a gradient coating of the NMC811 particles with lithium oxy-thiophosphate (Li3P1+xO4S4x). Via atomic layer deposition of Li3PO4 and subsequent in situ formation of a gradient Li3P1+xO4S4x coating, a precise and conformal covering for NMC811 particles is obtained. The tailored surface structure and chemistry of NMC811 hinder the structural degradation associated with the layered-to-spinel transformation in the grain boundaries and effectively stabilize the cathode|solid electrolyte interface during cycling. Indeed, when tested in combination with an indium metal negative electrode and a Li10GeP2S12 solid electrolyte, the gradient oxy-thiophosphate-coated NCM811-based positive electrode enables the delivery of a specific discharge capacity of 128 mAh/g after almost 250 cycles at 0.178 mA/cm2 and 25 °C.

18.
Angew Chem Int Ed Engl ; 62(3): e202216062, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36412226

RESUMO

A fundamental understanding of the nature of nuclearity effects is important for the rational design of superior sub-nanocatalysts with low nuclearity, but remains a long-standing challenge. Using atomic layer deposition, we precisely synthesized Fe sub-nanocatalysts with tunable nuclearity (Fe1 -Fe4 ) anchored on N,O-co-doped carbon nanorods (NOC). The electronic properties and spin configuration of the Fe sub-nanocatalysts were nuclearity dependent and dominated the H2 O2 activation modes and adsorption strength of active O species on Fe sites toward C-H oxidation. The Fe1 -NOC single atom catalyst exhibits state-of-the-art activity for benzene oxidation to phenol, which is ascribed to its unique coordination environment (Fe1 N2 O3 ) and medium spin state (t2g 4 eg 1 ); turnover frequencies of 407 h-1 at 25 °C and 1869 h-1 at 60 °C were obtained, which is 3.4, 5.7, and 13.6 times higher than those of Fe dimer, trimer, and tetramer catalysts, respectively.

19.
Virus Res ; 323: 199004, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36402209

RESUMO

Emerging evidence indicates that gut virome plays a role in human health and disease, however, much less is known about the viral communities in blood. Here we conducted a direct metatranscriptomic sequencing of virus-like-particles in blood from 1200 healthy individuals, without prior amplification to avoid potential amplification bias and with a strictly bioinformatic and manual check for candidate viral reads to reduce false-positive matches. We identified 55 different viruses from 36 viral families, including 24 human DNA, RNA and retroviruses in 70% of the studied pools. The study showed that anelloviruses are widely distributed and dominate the blood virome in healthy individuals. Human herpesviruses and pegivirus-1 are commonly prevalent in asymptomatic humans. We identified the prevalence of RNA viruses often causing acute infection, like HEV, HPIV, RSV and HCoV-HKU1, revealing of a transmissible risk of asymptomatic infection. Several viruses possible related to transfusion safety were identified, including human Merkel cell polyomavirus, papillomavirus, parvovirus B19 and herpesvirus 8 in addition to HBV. In addition, phages in Caudovirales and Microviridae, were commonly found in pools of samples with a very low abundance; a few sequences for invertebrate, plant and giant viruses were found in some of individuals; however, the remaining 31 viruses mostly reflect extensive contamination from commercial reagents and the work environments. In conclusion, this study is the first comprehensive investigation of blood virome in healthy individuals by metatranscriptomic sequencing of VLP in China. Further investigation of potential false positives representing a major challenge for the identification of novel viruses in mNGS, will offer a systemic idea and means to reveal true viral infections of human.

20.
Chem Commun (Camb) ; 58(94): 13155-13158, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36350262

RESUMO

Herein, ultrathin MoS2 flakes were prepared using a synergistic liquid phase precipitation method by applying ultrasound and microwave simultaneously. At 10 mA cm2 of electric current density, the MoS2 electrocatalysts' passing points are 176 mV and 154 mV respectively in acidic and alkaline electrolytes. This research provides a new synthetic method and potential opportunity in the design and preparation of multiple synergistic high-efficiency electrocatalysts.

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