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1.
Mol Biol Rep ; 51(1): 402, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456942

RESUMO

BACKGROUND: Acetyl-CoA carboxylase (ACC) catalyzes the carboxylation of acetyl-CoA to malonyl-CoA. Malonyl-CoA, which plays a key role in regulating glucose and lipid metabolism, is not only a substrate for fatty acid synthesis but also an inhibitor of the oxidation pathway. ACC exists as two isoenzymes that are encoded by two different genes. ACC1 in grass carp (Ctenopharyngodon idellus) has been cloned and sequenced. However, studies on the cloning, tissue distribution, and function of ACC2 in grass carp were still rare. METHODS AND RESULTS: The full-length cDNA of acc2 was 8537 bp with a 7146 bp open reading frame encoding 2381 amino acids. ACC2 had a calculated molecular weight of 268.209 kDa and an isoelectric point of 5.85. ACC2 of the grass carp shared the closest relationship with that of the common carp (Sinocyclocheilus grahami). The expressions of acc1 and acc2 mRNA were detected in all examined tissues.  The expression level of acc1 was high in the brain and fat but absent in the midgut and hindgut. The expression level of acc2 in the kidney was significantly higher than in other tissues, followed by the heart, brain, muscle, and spleen. ACCs inhibitor significantly reduced the levels of glucose, malonyl-CoA, and triglyceride in hepatocytes. CONCLUSIONS: This study showed that the function of ACC2 was evolutionarily conserved from fish to mammals. ACCs inhibitor inhibited the biological activity of ACCs, and reduced fat accumulation in grass carp.


Assuntos
Carpas , Animais , Carpas/genética , Carpas/metabolismo , Clonagem Molecular , Sequência de Bases , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Expressão Gênica , Glucose , Mamíferos/metabolismo
2.
Sensors (Basel) ; 24(5)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38475179

RESUMO

False data injection attacks (FDIAs) on sensor networks involve injecting deceptive or malicious data into the sensor readings that cause decision-makers to make incorrect decisions, leading to serious consequences. With the ever-increasing volume of data in large-scale sensor networks, detecting FDIAs in large-scale sensor networks becomes more challenging. In this paper, we propose a framework for the distributed detection of FDIAs in large-scale sensor networks. By extracting the spatiotemporal correlation information from sensor data, the large-scale sensors are categorized into multiple correlation groups. Within each correlation group, an autoregressive integrated moving average (ARIMA) is built to learn the temporal correlation of cross-correlation, and a consistency criterion is established to identify abnormal sensor nodes. The effectiveness of the proposed detection framework is validated based on a real dataset from the U.S. smart grid and simulated under both the simple FDIA and the stealthy FDIA strategies.

3.
Adv Mater ; : e2400622, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489844

RESUMO

Existing tear sensors are difficult to perform multiplexed assays due to the minute amounts of biomolecules in tears and the tiny volume of tears. Herein, the authors leverage DNA tetrahedral frameworks (DTFs) modified on the wireless portable electrodes to effectively capture 3D hybridization chain reaction (HCR) amplifiers for automatic and sensitive monitoring of multiple cytokines in human tears. The developed sensors allow the sensitive determination of various dry eye syndrome (DES)-associated cytokines in human tears with the limit of detection down to 0.1 pg mL-1, consuming as little as 3 mL of tear fluid. Double-blind testing of clinical DES samples using the developed sensor and commercial ELISA shows no significant difference between them. Compared with single-biomarker diagnosis, the diagnostic accuracy of this sensor based on multiple biomarkers has improved by ≈16%. The developed system offers the potential for tear sensors to enable personalized and accurate diagnosis of various ocular diseases.

4.
J Imaging Inform Med ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548992

RESUMO

We proposed an end-to-end deep learning convolutional neural network (DCNN) for region-of-interest based multi-parameter quantification (RMQ-Net) to accelerate quantitative ultrashort echo time (UTE) MRI of the knee joint with automatic multi-tissue segmentation and relaxometry mapping. The study involved UTE-based T1 (UTE-T1) and Adiabatic T1ρ (UTE-AdiabT1ρ) mapping of the knee joint of 65 human subjects, including 20 normal controls, 29 with doubtful-minimal osteoarthritis (OA), and 16 with moderate-severe OA. Comparison studies were performed on UTE-T1 and UTE-AdiabT1ρ measurements using 100%, 43%, 26%, and 18% UTE MRI data as the inputs and the effects on the prediction quality of the RMQ-Net. The RMQ-net was modified and retrained accordingly with different combinations of inputs. Both ROI-based and voxel-based Pearson correlation analyses were performed. High Pearson correlation coefficients were achieved between the RMQ-Net predicted UTE-T1 and UTE-AdiabT1ρ results and the ground truth for segmented cartilage with acceleration factors ranging from 2.3 to 5.7. With an acceleration factor of 5.7, the Pearson r-value achieved 0.908 (ROI-based) and 0.945 (voxel-based) for UTE-T1, and 0.733 (ROI-based) and 0.895 (voxel-based) for UTE-AdiabT1ρ, correspondingly. The results demonstrated that RMQ-net can significantly accelerate quantitative UTE imaging with automated segmentation of articular cartilage in the knee joint.

5.
Exp Mol Med ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556546

RESUMO

Acute liver injury is the basis of the pathogenesis of diverse liver diseases. However, the mechanism underlying liver injury is complex and not completely understood. In our study, we revealed that CERK, which phosphorylates ceramide to produce ceramide-1-phosphate (C1P), was the sphingolipid pathway-related protein that had the most significantly upregulated expression during acute liver injury. A functional study confirmed that CERK and C1P attenuate hepatic injury both in vitro and in vivo through antioxidant effects. Mechanistic studies have shown that CERK and C1P positively regulate the protein expression of NRF2, which is a crucial protein that helps maintain redox homeostasis. Furthermore, our results indicated that C1P disrupted the interaction between NRF2 and KEAP1 by competitively binding to KEAP1, which allowed for the nuclear translocation of NRF2. In addition, pull-down assays and molecular docking analyses revealed that C1P binds to the DGR domain of KEAP1, which allows it to maintain its interaction with NRF2. Importantly, these findings were verified in human primary hepatocytes and a mouse model of hepatic ischemia‒reperfusion injury. Taken together, our findings demonstrated that CERK-mediated C1P metabolism attenuates acute liver injury via the binding of C1P to the DGR domain of KEAP1 and subsequently the release and nuclear translocation of NRF2, which activates the transcription of cytoprotective and antioxidant genes. Our study suggested that the upregulation of CERK and C1P expression may serve as a potential antioxidant strategy to alleviate acute liver injury.

6.
ACS Appl Bio Mater ; 7(4): 2499-2510, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38517141

RESUMO

As important biomarkers of many diseases, glycoproteins are of great significance to biomedical science. It is essential to develop efficient glycoprotein enrichment platforms and investigate their adsorption mechanism. In this work, a conspicuous enrichment strategy for glycoproteins was developed by using an electrospun fiber membrane wrapped with polydopamine (PDA) and modified with 3-aminophenylboronic acid and nickel ions, named PAN/DA@PDA@APBA/Ni. The enrichment characteristics of PAN/DA@PDA@APBA/Ni toward glycoproteins were explored through adsorption behavior. Thanks to the existence of two sites of interaction (metal ion chelation and boronate affinity), PAN/DA@PDA@APBA/Ni exhibited significant enrichment capacity for glycoproteins, ovalbumin (604.6 mg/g), and human immunoglobulin G (331.0 mg/g). The adsorption kinetic results of glycoprotein ovalbumin on PAN/DA@PDA@APBA/Ni conform to the pseudo-first-order kinetic model in the first adsorption stage, while the second half adsorption stage is more in line with the pseudo-second-order kinetic model. Moreover, the physical characteristics of PAN/DA@PDA@APBA/Ni and subsequent adsorption experiments on electrospun fiber modified with only phenylboronic acid or nickel ions both confirmed two sites of interaction (metal ion chelation and boronate affinity, respectively). Furthermore, a stepwise elution method with dual-affinity interaction was designed and successfully applied to enrich glycoproteins in real biological samples. This work provides an idea for sample pretreatment, especially for the design of dual-affinity materials in glycoproteins enrichment.


Assuntos
Glicoproteínas , Níquel , Humanos , Ovalbumina , Adsorção , Íons
7.
Angew Chem Int Ed Engl ; : e202401206, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469979

RESUMO

Alloying nanoclusters (NCs) has emerged as a widely explored and versatile strategy for tailoring tunable properties, facilitating in-depth atomic-level investigations of structure-property correlations. In this study, we have successfully synthesized six atomically precise copper NCs alloyed with Group 10 metals (Pd or Pt). Notably, the Pd0 or Pt0 atom situated at the center of the distorted hexagonal antiprism Pd0/Pt0@Cu12 cage, coordinated with twelve Cu+ and two tBuC≡C- ligands. Moreover, ligand exchange strategies demonstrated the potential for Cl- and Br- to replace one or two alkynyl ligands positioned at the top or side of the NCs. The chirality exhibited by these racemic NCs is primarily attributed to the involvement of halogens and a chiral (Pd/Pt)@Cu18 skeleton. Furthermore, all the NCs exhibit near-infrared (NIR) luminescence, characterized by emission peaks at 705-755 nm, lifetimes ranging from 6.630 to 9.662 µs, and absolute photoluminescence quantum yields (PLQYs) of 1.75 %-2.52 % in their crystalline state. The experimental optical properties of these NCs are found to be in excellent agreement with the results of theoretical calculations. These alloy NCs not only offer valuable insights into the synthesis of Pd0/Pt0-Cu alloy NCs, but also bridge the gap in understanding the structure-luminescence relationships of Pd0/Pt0-Cu molecules.

8.
Nat Commun ; 15(1): 2450, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503743

RESUMO

Single-atom magnetism switching is a key technique towards the ultimate data storage density of computer hard disks and has been conceptually realized by leveraging the spin bistability of a magnetic atom under a scanning tunnelling microscope. However, it has rarely been applied to solid-state transistors, an advancement that would be highly desirable for enabling various applications. Here, we demonstrate realization of the electrically controlled Zeeman effect in Dy@C84 single-molecule transistors, thus revealing a transition in the magnetic moment from 3.8 µ B to 5.1 µ B for the ground-state GN at an electric field strength of 3 - 10 MV/cm. The consequent magnetoresistance significantly increases from 600% to 1100% at the resonant tunneling point. Density functional theory calculations further corroborate our realization of nonvolatile switching of single-atom magnetism, and the switching stability emanates from an energy barrier of 92 meV for atomic relaxation. These results highlight the potential of using endohedral metallofullerenes for high-temperature, high-stability, high-speed, and compact single-atom magnetic data storage.

9.
Sci Rep ; 14(1): 7054, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528084

RESUMO

Many intrusion detection techniques have been developed to ensure that the target system can function properly under the established rules. With the booming Internet of Things (IoT) applications, the resource-constrained nature of its devices makes it urgent to explore lightweight and high-performance intrusion detection models. Recent years have seen a particularly active application of deep learning (DL) techniques. The spiking neural network (SNN), a type of artificial intelligence that is associated with sparse computations and inherent temporal dynamics, has been viewed as a potential candidate for the next generation of DL. It should be noted, however, that current research into SNNs has largely focused on scenarios where limited computational resources and insufficient power sources are not considered. Consequently, even state-of-the-art SNN solutions tend to be inefficient. In this paper, a lightweight and effective detection model is proposed. With the help of rational algorithm design, the model integrates the advantages of SNNs as well as convolutional neural networks (CNNs). In addition to reducing resource usage, it maintains a high level of classification accuracy. The proposed model was evaluated against some current state-of-the-art models using a comprehensive set of metrics. Based on the experimental results, the model demonstrated improved adaptability to environments with limited computational resources and energy sources.

10.
Oral Oncol ; 150: 106715, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340546

RESUMO

Solitary fibrous tumor (SFT) represents an uncommon spindle cell sarcoma predominantly situated within soft tissue, with a notably infrequent occurrence in the nasal cavity and paranasal sinuses. In this report, we present a case involving a middle-aged male with a sizable solitary fibrous tumor affecting both the nasal and oral cavities.


Assuntos
Neoplasias Nasais , Seios Paranasais , Sarcoma , Tumores Fibrosos Solitários , Pessoa de Meia-Idade , Humanos , Masculino , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/patologia , Tumores Fibrosos Solitários/diagnóstico , Seios Paranasais/patologia , Cavidade Nasal/patologia , Sarcoma/patologia
11.
Biochim Biophys Acta Mol Basis Dis ; 1870(4): 167088, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401696

RESUMO

Acute pancreatitis (AP) can lead to death; however, there is no specific treatment for AP. Screening of drugs for AP treatment is rarely performed. Compounds were screened in a primary pancreatic acinar cell and peritoneal macrophage coculture system. Compounds were used in vitro and in vivo. Compound targets were predicted and validated. Among the 18 nitrogen-containing heterocycles, Z10 was shown to decrease the cerulein plus lipopolysaccharide (CL)-induced secretion of both acinar digestive enzymes and macrophage cytokines. Z10 was also shown to ameliorate CL-induced or sodium taurocholate-induced AP in mice. Proteomics analysis and enzyme linked immunosorbent assay (ELISA) revealed that Z10 decreased the levels of D-dopachrome tautomerase (Ddt) within macrophages and those in the extracellular milieu under CL treatment. Z10 also decreased Ddt expression in AP mice. Moreover, exogenous Ddt induced cytokine and digestive enzyme secretion, which could be inhibited by Z10. Ddt knockdown inhibited CL-induced cytokine secretion. Medium from CL-treated macrophages induced the release of amylase by acinar cells, and Ddt knockdown medium decreased amylase secretion. The target of Z10 was predicted to be ERK2. Z10 increased the thermostability of ERK1/2 but not ERK1 K72A/ERK2 K52A. The docking poses of ERK1 and ERK2 with Z10 were similar. Z10 inhibited ERK1/2 phosphorylation, and Ddt levels and cytokines were regulated by ERK1/2 during AP. Additionally, Z10 could not further inhibit cytokines under ERK1/2 knockdown with CL. Thus, this study revealed that Z10-mediated ERK1/2 inhibition decreased Ddt expression and secretion by macrophages. Ddt inhibition decreased cytokine release and digestive enzyme secretion.


Assuntos
Pancreatite , Camundongos , Animais , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Doença Aguda , Citocinas , Amilases/efeitos adversos , Pirazóis
12.
Clin Ther ; 46(3): 252-257, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38368167

RESUMO

PURPOSE: During the induction of general anesthesia, opioids and endotracheal intubation may cause coughing. This study aimed to investigate the safety and effectiveness of an optimized drug induction scheme for general anesthesia to prevent coughing in patients. METHODS: A total of 220 patients aged 18 to 65 years who underwent surgery under general anesthesia with endotracheal intubation were randomly assigned to two groups, each with 110 patients. One group was administered a divided sufentanil bolus (group A) and the other with a single sufentanil bolus (group B). Anesthesia induction was performed according to the drug induction scheme of 1st, 2nd, and 3rd minutes. The primary outcome was a coughing episode associated with the administration of opioids during anesthesia induction. We also recorded the pain associated with drug injection, hemodynamics, and blood oxygen saturation during the induction of anesthesia. FINDINGS: All patients were included in the final statistical analysis. Compared with group B, the incidence of opioid induced cough (OIC) was significantly higher in group A (9.1% vs. 0, P = 0.001). There was no cough reaction of tracheal intubation in either group. There was no severe pain due to propofol and rocuronium injection in either group (P > 0.05). The mean arterial pressure (MAP), heart rate (HR), and peripheral oxygen saturation (SpO2) values were within the normal range at each time point during the induction period in both groups. IMPLICATIONS: According to the optimized 1st, 2nd, and 3rd minutes anesthesia induction regimen, with a single final intravenous bolus of sufentanil after the diluted rocuronium bromide administration, no sufentanil and tracheal intubation induced coughing reactions were observed. TRIAL REGISTRATION: The study protocol was registered in the Chinese Clinical Trial Registry (ChiCTR2200062749, http://www.chictr.org.cn/showproj.aspx?proj=175018) on August 17, 2022.


Assuntos
Analgésicos Opioides , Sufentanil , Humanos , Sufentanil/efeitos adversos , Estudos Prospectivos , Analgésicos Opioides/uso terapêutico , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Dor/tratamento farmacológico , Tosse/induzido quimicamente , Tosse/prevenção & controle
13.
Dalton Trans ; 53(7): 3244-3253, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38251847

RESUMO

Four copper(II)-plumbagin and -bipyridine complexes (Cu1-Cu4) were synthesized as chemodynamic therapy agents with enhanced antitumor activity. As lipophilic and positively charged compounds, Cu1-Cu4 were preferentially accumulated in mitochondria and activated the mitochondrial apoptosis pathway. Mechanistic studies showed that Cu1-Cu4 reacted with GSH to reduce Cu2+ ions to Cu+ ions, catalyzed the formation of toxic hydroxyl radicals (˙OH) from hydrogen peroxide (H2O2) through a Fenton-like reaction, induced mitochondrial dysfunction, and activated caspase-9/3, which eventually led to apoptosis. Cu1-Cu4 arrested HeLa cells in the S phase and eventually killed cancer cells. Cu2 showed a favorable pharmacokinetic profile in mice. Moreover, Cu2 effectively inhibited the growth of HeLa xenografts in nude mice and showed low toxicity in vivo.


Assuntos
Cobre , Naftoquinonas , Neoplasias , Humanos , Animais , Camundongos , Cobre/metabolismo , Peróxido de Hidrogênio/metabolismo , Células HeLa , Camundongos Nus , Mitocôndrias/metabolismo , Linhagem Celular Tumoral , Neoplasias/metabolismo , Glutationa/metabolismo
14.
Small ; : e2310743, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263812

RESUMO

Chronic wounds have emerged as an increasingly critical clinical challenge over the past few decades, due to their increasing incidence and socioeconomic burdens. Platelet-derived growth factor (PDGF) plays a pivotal role in regulating processes such as fibroblast migration, proliferation, and vascular formation during the wound healing process. The delivery of PDGF offers great potential for expediting the healing of chronic wounds. However, the clinical effectiveness of PDGF in chronic wound healing is significantly hampered by its inability to maintain a stable concentration at the wound site over an extended period. In this study, a controlled PDGF delivery system based on nanocapsules is proposed. In this system, PDGF is encapsulated within a degradable polymer shell. The release rate of PDGF from these nanocapsules can be precisely adjusted by controlling the ratios of two crosslinkers with different degradation rates within the shells. As demonstrated in a diabetic wound model, improved therapeutic outcomes with PDGF nanocapsules (nPDGF) treatment are observed. This research introduces a novel PDGF delivery platform that holds promise for enhancing the effectiveness of chronic wound healing.

15.
J Inorg Biochem ; 251: 112432, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38016329

RESUMO

The combination of mitochondrial targeting and chemodynamic therapy is a promising anti-cancer strategy. Three mitochondria targeting copper(II) complexes (Cu1-Cu3) with plumbagin and bipyridine ligands for enhanced chemodynamic therapy were synthesized and characterized. Their anti-proliferative activity to HeLa cells was higher than that of cisplatin, and their toxicity to normal cells was low. Cellular uptake and distribution studies indicated that Cu1 and Cu3 were mainly accumulated in mitochondria. The mechanism studies showed that Cu1 and Cu3 converted intracellular H2O2 into toxic hydroxyl radicals by consuming glutathione, leading to mitochondrial dysfunction. Treatment with the copper complex caused ER stress and cell arrest in the S phase which resulted in apoptosis. In vivo, Cu1 and Cu3 effectively inhibited the growth of HeLa xenograft tumors without obvious toxic and side effects.


Assuntos
Cobre , Neoplasias , Humanos , Células HeLa , Cobre/farmacologia , Peróxido de Hidrogênio/farmacologia , Mitocôndrias , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
16.
Adv Mater ; 36(6): e2306244, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37815787

RESUMO

Restricted by the available energy storage modes, currently rechargeable aluminum-ion batteries (RABs) can only provide a very limited experimental capacity, regardless of the very high gravimetric capacity of Al (2980 mAh g-1 ). Here, a novel complexation mechanism is reported for energy storage in RABs by utilizing 0D fullerene C70 as the cathode. This mechanism enables remarkable discharge voltage (≈1.65 V) and especially a record-high reversible specific capacity (750 mAh g-1 at 200 mA g-1 ) of RABs. By means of in situ Raman monitoring, mass spectrometry, and density functional theory (DFT) calculations, it is found that this elevated capacity is attributed to the direct complexation of one C70 molecule with 23.5 (super)halogen moieties (superhalogen AlCl4 and/or halogen Cl) in average, forming (super)halogenated C70 ·(AlCl4 )m Cln-m complexes. Upon discharging, decomplexation of C70 ·(AlCl4 )m Cln-m releases AlCl4 - /Cl- ions while preserving the intact fullerene cage. This work provides a new route to realize high-capacity and long-life batteries following the complexation mechanism.

17.
Plant Cell Environ ; 47(1): 259-277, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37691629

RESUMO

Phosphorus (P) is an essential nutrient, but easily fixed in soils. Therefore, most of soil P exists in the form of inaccessible organic phosphorus (Po), particularly phytate-P. Root-associated purple acid phosphatases (PAPs) are considered to play a crucial role in phosphate (Pi) scavenging in soils. However, evidence for regulating root-associated PAPs in utilization of extracellular phytate-P remain largely unknown in plants at both transcriptional and posttranslational levels. In this study, a Pi-starvation responsive GmPAP15a was identified in soybean (Glycine max). Overexpressing GmPAP15a led to significant increases in root-associated phytase activities, as well as total P content when phytate-P was supplied as the sole P resource in soybean hairy roots. Meanwhile, mass spectrometry (MS) analysis showed GmPAP15a was glycosylated at Asn144 and Asn502 , and its glycan structures of N-linked oligosaccharide chains exhibited microheterogeneity. Moreover, two homologues of AtPHR1, GmPHR9 and GmPHR32 were found to activate GmPAP15a transcription through luciferase activity analysis. Taken together, it is strongly suggested that GmPAP15a plays a vital role in phytate-P utilization in soybean, which might be regulated at both transcriptional and glycosylation modification levels. Our results highlight the GmPHR9/GmPHR32-GmPAP15a signalling pathway might present, and control phytate-P utilization in soybean.


Assuntos
Soja , Ácido Fítico , Soja/metabolismo , Glicosilação , Ácido Fítico/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Fósforo/metabolismo , Solo
18.
Molecules ; 28(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38067634

RESUMO

Peroxyacetic acid (PAA)-based advanced oxidation processes (AOPs) have attracted much attention in wastewater treatment by reason of high selectivity, long half-life reactive oxygen species (ROS), and wider applicability. In this study, cobalt ferrite (CoFe2O4) was applied to activate PAA for the removal of ofloxacin (OFX). The degradation of OFX could reach 83.0% via the CoFe2O4/PAA system under neutral conditions. The low concentration of co-existing anions and organic matter displayed negligible influence on OFX removal. The contributions of hydroxyl radicals (·OH), organic radicals (R-O·), and other reactive species to OFX degradation in CoFe2O4/PAA were systematically evaluated. Organic radicals (especially CH3C(O)OO·) and singlet oxygen (1O2) were verified to be the main reactive species leading to OFX destruction. The Co(II)/Co(III) redox cycle occurring on the surface of CoFe2O4 played a significant role in PAA activation. The catalytic performance of CoFe2O4 remained above 80% after five cycles. Furthermore, the ecotoxicity of OFX was reduced after treatment with the CoFe2O4/PAA system. This study will facilitate further research and development of the CoFe2O4/PAA system as a new strategy for wastewater treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio , Ácido Peracético , Ofloxacino , Oxirredução
19.
J Chem Phys ; 159(24)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38131484

RESUMO

Endohedral metal-metal-bonding fullerenes have recently emerged, in which encapsulated metals form a metal-metal bond. However, the physical reasons why some metal elements prefer to form metal-metal bonds inside fullerene are still unclear. Herein, we reported first-principles calculations on electronic structures, bonding properties, dynamics, and thermodynamic stabilities of endohedral metallofullerenes M2@C82 (M = Sc, Y, La, Lu). Multiple bonding analysis approaches unambiguously reveal the existence of one two-center two-electron σ covalent metal-metal bond in M2@C82 (M = Sc, Y, Lu); however, the La-La bonding interaction in La2@C82 is weaker and could not be categorized as one metal-metal covalent bond. The energy decomposition analysis on bonding interactions between an encapsulated metal dimer and fullerene cages suggested that there exist two electron-sharing bonds between a metal dimer and fullerene cages. The reasons why La2 prefers to donate electrons to fullerene cages rather than form a standard σ covalent metal-metal bond are mainly attributed to two following facts: La2 has a lower ionization potential, while the hybridization of ns, (n - 1)d, and np atomic orbitals in La2 is higher. Ab initio molecular dynamic simulations reveal that the M-M bond length at room temperature follows the trend of Sc < Lu < Y. The statistical thermodynamics calculations at different temperatures reveal that the experimentally observed endohedral metal-metal-bonding fullerenes M2@C82 have high concentrations in the endohedral fullerene formation temperature range.

20.
Nat Commun ; 14(1): 8443, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114506

RESUMO

Reducing inter-spin distance can enhance magnetic interactions and allow for the realization of outstanding magnetic properties. However, achieving reduced distances is technically challenging. Here, we construct a 3d-4f metal cluster (Dy2VN) inside a C80 cage, affording a heretofore unseen metallofullerene containing both paramagnetic 3d and 4f metal ions. The significantly suppressed 3d-4f (Dy-V) distances, due to the unique cage confinement effect, were observed by crystallographic and theoretical analysis of Dy2VN@Ih(7)-C80. These reduced distances result in an enhanced magnetic coupling (Jtotal, Dy-V = 53.30 cm-1; Jtotal, Dy-Dy = -6.25 cm-1), leading to a high magnetic blocking temperature compared to reported 3d-4f single-molecule magnets and strong coercive field of 2.73 Tesla. Our work presents a new class of single-molecule magnets with both paramagnetic 3d and 4f metals confined in a fullerene cage, offering superior and tunable magnetic properties due to the unique cage confinement effect and the diverse composition of the entrapped magnetic core.

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