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Inhibition of the tumour suppressive function of p53 (encoded by TP53) is paramount for cancer development in humans. However, p53 remains unmutated in the majority of cases of glioblastoma (GBM)-the most common and deadly adult brain malignancy1,2. Thus, how p53-mediated tumour suppression is countered in TP53 wild-type (TP53WT) GBM is unknown. Here we describe a GBM-specific epigenetic mechanism in which the chromatin regulator bromodomain-containing protein 8 (BRD8) maintains H2AZ occupancy at p53 target loci through the EP400 histone acetyltransferase complex. This mechanism causes a repressive chromatin state that prevents transactivation by p53 and sustains proliferation. Notably, targeting the bromodomain of BRD8 displaces H2AZ, enhances chromatin accessibility and engages p53 transactivation. This in turn enforces cell cycle arrest and tumour suppression in TP53WT GBM. In line with these findings, BRD8 is highly expressed with H2AZ in proliferating single cells of patient-derived GBM, and is inversely correlated with CDKN1A, a canonical p53 target that encodes p21 (refs. 3,4). This work identifies BRD8 as a selective epigenetic vulnerability for a malignancy for which treatment has not improved for decades. Moreover, targeting the bromodomain of BRD8 may be a promising therapeutic strategy for patients with TP53WT GBM.
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Epigênese Genética , Glioblastoma , Fatores de Transcrição , Proteína Supressora de Tumor p53 , Adulto , Humanos , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proliferação de CélulasRESUMO
The simple and low-cost construction of a 3D network structure is an ideal way to prepare high-performance electromagnetic wave (EMW) absorption materials. Herein, a series of carbon skeleton/carbon nanotubes/Ni3ZnC0.7 composites (CS/CNTs/Ni3ZnC0.7) are successfully prepared by in situ growth of Ni3ZnC0.7 and CNTs on 3D melamine sponge carbon. With the increase of precursor, Ni3ZnC0.7 nanoparticles nucleate and catalyze the generation of CNTs on the surface of the carbon skeleton. The minimum reflection loss (RL) value of the S60min composite (loading time of 60 min) reaches -86.6 dB at 1.6 mm and effective absorption bandwidth (EAB, RL≤-10 dB) is up to 9.3 GHz (8.7-18 GHz). The 3D network sponge carbon with layered micro/nanostructure and hollow skeleton promotes multiple reflection and absorption mechanisms of incident EMW. The N-doping and defects can be equivalent to an electric dipole, providing dipole polarization to increase dielectric relaxation. The uniform Ni3ZnC0.7 nanoparticles and CNTs play a key role in dissipating electromagnetic energy, blocking heat transfer, and enhancing the mechanical properties of the skeleton. Fortunately, the composite displays a quite low thermal conductivity of 0.09075 W m·K-1 and good flexibility, which can provide insulation and quickly recover to its original state after being stressed.
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The efficient removal of radioactive uranium from aqueous solution is of great significance for the safe and sustainable development of nuclear power. An ultrathin 2D metal-organic framework (MOF) nanosheet with cavity structures was elaborately fabricated based on a calix[4]arene ligand. Incorporating the permanent cavity structures on MOF nanosheet can fully utilize its structural characteristics of largely exposed surface area and accessible adsorption sites in pollutant removal, achieving ultrafast adsorption kinetics, and the functionalized cavity structure would endow the MOF nanosheets with the ability to achieve preconcentration and extraction of uranium from aqueous solution, affording ultrahigh removal efficiency even in ultra-low concentrations. Thus, more than 97% uranium can be removed from the concentration range of 50-500 µg L-1 within 5 min. Moreover, the 2D nano-material exhibits ultra-high anti-interference ability, which can efficiently remove uranium from groundwater and seawater. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) analysis, and density functional theory (DFT) calculations, which revealed that the cavity structure plays an important role in uranium capture. This study not only realizes highly efficient uranium removal from aqueous solution but also opens the door to achieving ultrathin MOF nanosheets with cavity structures, which will greatly expand the applications of MOF nanosheets.
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Reconstructing computed tomography (CT) images from an extremely limited set of projections is crucial in practical applications. As the available projections significantly decrease, traditional reconstruction and model-based iterative reconstruction methods become constrained. This work aims to seek a reconstruction method applicable to fast CT imaging when available projections are highly sparse. To minimize the time and cost associated with projections acquisition, we propose a deep learning model, X-CTReNet, which parameterizes a nonlinear mapping function from orthogonal projections to CT volumes for 3D reconstruction. The proposed model demonstrates effective capability in inferring CT volumes from two-view projections compared to baseline methods, highlighting the significant potential for drastically reducing projection acquisition in fast CT imaging.
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Pelodiscus sinensis meat is a nutritional food and tonic with angiotensin-converting enzyme (ACE) inhibitory activities. To identify the bioactive substances responsible, several bioinformatics methods were integrated to enable a virtual screening for bioactive peptides in proteins identified within a water-soluble protein fraction of Pelodiscus sinensis meat by Shotgun proteomics. The peptides were generated from the identified proteins by in silico proteolysis using six proteases. A comparison of the numbers of proteins suitable for digestion with each enzyme and the iBAQ (intensity-based absolute quantification) values for these proteins revealed that bromelain and papain were the most suitable proteases for this sample. Next, the water solubility, toxicity, and ADMET (absorption/distribution/metabolism/excretion/toxicity) properties of these peptides were evaluated in silico. Finally, a novel ACE inhibitory peptide IEWEF with an IC50 value of 41.33 µM was identified. The activity of the synthesized peptide was verified in vitro, and it was shown to be a non-competitive ACE inhibitor. Molecular docking revealed that IEWEF could tightly bind to C-ACE, and N-ACE with energies less than 0 kJ mol-1, and the peptide IEWEF can form hydrogen bonds with C-ACE and N-ACE respectively. These results provide evidence that bioactive peptides in the water-soluble protein fraction account for (at least) some of the ACE inhibitory activities observed in Pelodiscus sinensis meat. Furthermore, our research provides a workflow for the efficient identification of novel ACE inhibitory peptides from complex protein mixtures.
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Inibidores da Enzima Conversora de Angiotensina , Simulação de Acoplamento Molecular , Peptídeos , Hidrolisados de Proteína , Solubilidade , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Animais , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Água/química , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Papaína/metabolismo , Papaína/antagonistas & inibidores , Papaína/química , Proteínas de Peixes/química , Proteínas de Peixes/metabolismoRESUMO
The hierarchical Cu2 S@NC@MoS3 heterostructures have been firstly constructed by the high-capacity MoS3 and high-conductive N-doped carbon to co-decorate the Cu2 S hollow nanospheres. During the heterostructure, the middle N-doped carbon layer as the linker facilitates the uniform deposition of MoS3 and enhances the structural stability and electronic conductivity. The popular hollow/porous structures largely restrain the big volume changes of active materials. Due to the cooperative effect of three components, the new Cu2 S@NC@MoS3 heterostructures with dual heterogenous interfaces and small voltage hysteresis for sodium ion storage display a high charge capacity (545 mAh g-1 for 200 cycles at 0.5 A g-1 ), excellent rate capability (424 mAh g-1 at 15 A g-1 ) and ultra-long cyclic life (491 mAh g-1 for 2000 cycles at 3 A g-1 ). Except for the performance test, the reaction mechanism, kinetics analysis, and theoretical calculation have been performed to explain the reason of excellent electrochemical performance of Cu2 S@NC@MoS3 . The rich active sites and rapid Na+ diffusion kinetics of this ternary heterostructure is beneficial to the high efficient sodium storage. The assembled full cell matched with Na3 V2 (PO4 )3 @rGO cathode likewise displays remarkable electrochemical properties. The outstanding sodium storage performances of Cu2 S@NC@MoS3 heterostructures indicate the potential applications in energy storage fields.
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BACKGROUND: The swift shift toward internet hospitals has relied on the willingness of medical practitioners to embrace new systems and workflows. Low engagement or acceptance by medical practitioners leads to difficulties in patient access. However, few investigations have focused on barriers and facilitators of adoption of internet hospitals from the perspective of medical practitioners. OBJECTIVE: This study aims to identify both enabling and inhibiting predictors associated with resistance and behavioral intentions of medical practitioners to use internet hospitals by combining the conservation of resources theory with the Unified Theory of Acceptance and Use of Technology and technostress framework. METHODS: A mixed methods research design was conducted to qualitatively identify the factors that enable and inhibit resistance and behavioral intention to use internet hospitals, followed by a quantitative survey-based study that empirically tested the effects of the identified factors. The qualitative phase involved conducting in-depth interviews with 16 experts in China from June to August 2022. Thematic analysis was performed using the qualitative data analysis software NVivo version 10 (QSR International). On the basis of the findings and conceptual framework gained from the qualitative interviews, a cross-sectional, anonymous, web-based survey of 593 medical practitioners in 28 provincial administrative regions of China was conducted. The data collected were analyzed using the partial least squares method, with the assistance of SPSS 27.0 (IBM Corp) and Mplus 7.0 (Muthen and Muthen), to measure and validate the proposed model. RESULTS: On the basis of qualitative results, this study identified 4 facilitators and inhibitors, namely performance expectancy, social influence, work overload, and role ambiguity. Of the 593 medical practitioners surveyed in the quantitative research, most were female (n=364, 61.4%), had a middle title (n=211, 35.6%) or primary title (n=212, 35.8%), and had an average use experience of 6 months every year. By conducting structural equation modeling, we found that performance expectancy (ß=-.55; P<.001) and work overload (ß=.16; P=.005) had the most significant impact on resistance to change. Resistance to change fully mediated the influence of performance expectancy and partially mediated the influences of social influence (variance accounted for [VAF]=43.3%; P=.002), work overload (VAF=37.2%; P=.03), and role ambiguity (VAF=12.2%; P<.001) on behavioral intentions to use internet hospitals. In addition, this study found that the sex, age, professional title, and use experience of medical practitioners significantly moderated the aforementioned influencing mechanisms. CONCLUSIONS: This study investigated the factors that facilitate or hinder medical practitioners' resistance to change and their behavioral intentions to use internet hospitals. The findings suggest that policy makers avoid the resistance and further promote the adoption of internet hospitals by ensuring performance expectancy and social influence and eliminating work overload and role ambiguity.
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Hospitais , Médicos , Humanos , Conhecimentos, Atitudes e Prática em Saúde , China , Intenção , Atitude do Pessoal de Saúde , InternetRESUMO
Two-dimensional (2D) metal-organic framework (MOF) nanosheets, with largely exposed surface area and highly accessible active sites, have emerged as a novel kind of sensing material. Here, a luminescent 2D MOF nanosheet was designed and synthesized by a facile top-down strategy based on a three-dimensional (3D) layered MOF {[Zn(H2L)(H2O)2]·H2O}n (Zn-MOF; H4L = 3,5-bis(3',5'-dicarboxyphenyl)-1H-1,2,4-triazole). With a large π-conjugated system and rigid planar structure, ligand H4L was elaborately selected to construct the bulk Zn-MOF, which can be readily exfoliated into 2D nanosheets, owing to the weak interlayer interactions and easy-to-release H2O molecules in the interspaces of 2D layers. Given the great threat posed to the ecological environment by anti-inflammatory drugs and pesticides, the developed luminescent Zn-MOF nanosheets were utilized to determine these organic pollutants, achieving highly selective and sensitive detection of diclofenac sodium (DCF) and tetramethylthiuram disulfide (TMTD). Compared to the detection limits of 3D Zn-MOF (7.72 ppm for DCF, 6.01 ppm for TMTD), the obviously lower detection limits for 2D Zn-MOF nanosheets toward DCF (0.20 ppm) and TMTD (0.18 ppm) further revealed that the largely exposed surface area with rigid planar structure and ultralarge π-conjugated system greatly accelerated electron transfer, which brought about a vast improvement in response sensitivity. The remarkable quenching performance for DCF and TMTD stems from a combined effect of photoinduced electron transfer and competitive energy absorption. The possible sensing mechanism was systematically investigated by the studies of powder X-ray diffraction, UV-vis, luminescence lifetime, and density functional theory calculations.
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Estruturas MetalorgânicasRESUMO
BACKGROUND: Patient safety incident (PSI) reporting has been an important means of improving patient safety and enhancing organizational quality control. Reports of anesthesia-related incidents are of great value for analysis to improve perioperative patient safety. However, the utilization of incident data is far from sufficient, especially in developing countries such as China. METHODS: All PSIs reported by anesthesiologists in a Chinese academic hospital between September 2009 and August 2019 were collected from the incident reporting system. We reviewed the freeform text reports, supplemented with information from the patient medical record system. Composition analysis and risk assessment were performed. RESULTS: In total, 847 PSIs were voluntarily reported by anesthesiologists during the study period among 452,974 anesthetic procedures, with a reported incidence of 0.17%. Patients with a worse ASA physical status were more likely to be involved in a PSI. The most common type of incident was related to the airway (N = 208, 27%), followed by the heart, brain and vascular system (N = 99, 13%) and pharmacological incidents (N = 79, 10%). Those preventable incidents with extreme or high risk were identified through risk assessment to serve as a reference for the implementation of more standard operating procedures by the department. CONCLUSIONS: This study describes the characteristics of 847 PSIs voluntarily reported by anesthesiologists within eleven years in a Chinese academic hospital. Airway incidents constitute the majority of incidents reported by anesthesiologists. Underreporting is common in China, and the importance of summarizing and utilizing anesthesia incident data should be scrutinized.
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Anestesia/efeitos adversos , Anestesiologistas/estatística & dados numéricos , Segurança do Paciente/estatística & dados numéricos , Assistência Perioperatória/métodos , Gestão de Riscos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Anestesia/métodos , China , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Adulto JovemRESUMO
ZnSe is regarded as a promising anode material for energy storage due to its high theoretical capacity and environment friendliness. Nevertheless, it is still a significant challenge to obtain superior electrode materials with stable performance owing to the serious volume change and aggregation upon cycling. Herein, a willow-leaf-like nitrogen-doped carbon-coated ZnSe (ZnSe@NC) composite synthesized through facile solvothermal and subsequent selenization process is beneficial to expose more active sites and facilitate the fast electron/ion transmission. These merits significantly enhance the electrochemical performances of ZnSe@NC for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). The obtained ZnSe@NC exhibits outstanding rate performance (440.3 mAh g-1 at 0.1 A g-1 and 144.4 mAh g-1 at 10 A g-1 ) and ultralong cycle stability (242.2 mAh g-1 at 8.0 A g-1 even after 3200 cycles) for SIBs. It is noted that 106.5 mAh g-1 can be retained after 550 cycles and 71.4 mAh g-1 is still remained after 1500 cycles at 200 mA g-1 when applied as anode for PIBs, indicating good cycle stability of the electrode. The possible electrochemical mechanism and the ionic diffusion kinetics of the ZnSe@NC are investigated using ex situ X-ray diffraction, high-resolution transmission electron microscopy, and a series of electrochemical analyses.
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Ovarian cancer (OC) is one of prevalent tumors and this study aimed to explore CCL20's effects on doxorubicin resistance of OC and related mechanisms. Doxorubicin-resistant SKOV3 DR cells were established from SKOV3 cells via 6-month continuous exposure to gradient concentrations of doxorubicin. Quantitative PCR and Western blot assay showed that SKOV3 DR cells had higher level of CCL20 than SKOV3 cells, and doxorubicin upregulated CCL20 expression in SKOV3 cells. MTT and cell count assay found that CCL20 overexpression plasmid enhanced doxorubicin resistance of SKOV3 and OVCA433 cells compared to empty vector, as shown by the increase in cell viability. In contrast, CCL20 shRNA enhanced doxorubicin sensitivity of SKOV3 DR cells compared to control. CCL20 overexpression plasmid promoted NF-kB activation and positively regulated ABCB1 expression. Besides, ABCB1 overexpression plasmid enhanced the viability of SKOV3 and OVCA433 cells compared to empty vector under treatment with the same concentration of doxorubicin, whereas ABCB1 shRNA inhibited doxorubicin resistance of SKOV3 DR cells compared to control. In conclusion, CCL20 enhanced doxorubicin resistance of OC cells by regulating ABCB1 expression.Key words: CCL20, ovarian cancer, doxorubicin resistance, tumor-promoting, ABCB1.
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Quimiocina CCL20/metabolismo , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/patologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
MicroRNA (miR)-204 is known to be associated with several different diseases. Polycystic ovary syndrome (PCOS) has the highest incidence rate among the endocrine disorders in females between the ages of 18 and 44. We aimed to illustrate the miR-204 function in PCOS. MiR-204 expression levels in tissue and cell were examined through RT-qPCR. Colony formation assay and MTT assay were applied to detect the cell viability. Flow cytometry was employed to examine the apoptosis and cell cycle in cells. RNA binding protein immunoprecipitation assay and luciferase reporter assay were provided to demonstrate the direct interaction between translationally controlled tumor protein (TPT1) and miR-204. The expression of miR-204 was declined in KGN cells and ovarian cortex tissues of PCOS patients. MiR-204 enhanced the colony formation capacity and cell proliferation in KGN cells. Cell cycle and apoptosis were also influenced by miR-204. Since miR-204 has direct interaction with TPT1, TPT1 overexpression suppressed the miR-204-induced apoptosis and cell cycle alteration in KGN cells. MiR-204 inhibits the cell viability and induces apoptosis and cell cycle arrest by directly interacting with TPT1, indicating a role of miR-204 to be a potential target in the PCOS patients.
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Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/antagonistas & inibidores , Células da Granulosa/efeitos dos fármacos , MicroRNAs/farmacologia , Ovário/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Biomarcadores Tumorais/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Células da Granulosa/metabolismo , Humanos , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Proteína Tumoral 1 Controlada por TraduçãoRESUMO
INTRODUCTION: Altered gene expression coincides with leukemia development and may affect distinct features of leukemic cells. PITHD1 was significantly downregulated in leukemia and upregulated upon PMA induction in K562 cells undergoing megakaryocyte differentiation. We aimed to study the function of PITHD1 in megakaryocyte differentiation. MATERIALS AND METHODS: K562 cells and fetal liver cells were used for either overexpression or downregulation of PITHD1 by retroviral or lentiviral transduction. FACS was used to detect the expression of CD41 and CD42 to measure megakaryocyte differentiation in these cells. Western blot and quantitative RT-PCR were used to measure gene expression. Dual luciferase assay was used to detect promoter or internal ribosomal entry site (IRES) activity. RESULTS: Ectopic expression of PITHD1 promoted megakaryocyte differentiation and increased RUNX1 expression while PITHD1 knockdown showed an opposite phenotype. Furthermore, PITHD1 efficiently induced endogenous RUNX1 expression and restored megakaryocyte differentiation suppressed by a dominant negative form of RUNX1. PITHD1 regulated RUNX1 expression at least through two distinct mechanisms: increasing transcription activity of proximal promoter and enhancing translation activity of an IRES element in exon 3. Finally, we confirmed the function of PITHD1 in regulating RUNX1 expression and megakaryopoiesis in mouse fetal liver cells. CONCLUSION AND SIGNIFICANCE: PITHD1 was a novel activator of IRES and enhanced RUNX1 expression that subsequently promoted megakaryocyte differentiation. Our findings shed light on understanding the mechanisms underlying megakaryopoiesis or leukemogenesis.
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Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Proteínas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação para Baixo , Flavonoides/farmacologia , Humanos , Células K562 , Fígado/citologia , Fígado/metabolismo , Megacariócitos/citologia , Megacariócitos/metabolismo , Camundongos , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Glicoproteína IIb da Membrana de Plaquetas/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/genética , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Regulação para CimaRESUMO
Photodynamic therapy provides a promising solution for treating various cancer types. In this study, three distinct asymmetric porphyrin-cisplatin complex photosensitizers (ZnPt-P1, ZnPt-P2, and ZnPt-P3) were synthesized, each having unique side chains. Through a set of experiments involving singlet oxygen detection and density functional theory, ZnPt-P1 was demonstrated to have excellent efficacy, exceeding that of ZnPt-P2 and ZnPt-P3. Notably, ZnPt-1 showed significant phototoxicity while maintaining low dark toxicity when tested on HepG2 cells. Additionally, further examination revealed that ZnPt-P1 had the capability to generate reactive oxygen species within cancer cells when exposed to light irradiation. Taken together, these results highlight the potential of ZnPt-P1 as a photosensitizer for use in photodynamic therapy. This study contributes to enhancing cancer treatment methodologies and provides insights for the future development of innovative drugs for photosensitization.
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Fotoquimioterapia , Porfirinas , Fármacos Fotossensibilizantes , Cisplatino/farmacologia , Porfirinas/química , Oxigênio Singlete/químicaRESUMO
Tailoring the omnidirectional conductivity networks in nickel oxide-based electrodes is important for ensuring their long lifespan, stability, high capacity, and high-rate capability. In this study, nickel metal nanoparticles and a three-dimensional nitrogen-doped carbon matrix were used to embellish the nickel oxide composite NiO-Ni/N-C via simplified hard templating. When a porous nitrogen-doped carbon matrix is present, a rapid pathway would be established for charging and discharging the electrons and lithium ions in a lithium-ion battery, thereby alleviating the volumetric expansion of the NiO nanoparticles during the operation of the battery. Moreover, the Ni0 ions added to serve as active sites to improve the capacity of the NiO-based electrodes and strengthen their conductivities. The multielement-effects of the optimal NiO-Ni/N-C electrode leads it to exhibit a capacity of 1310.8 mAh g-1 at 0.1 A g-1 for 120 loops and a rate capability of 441.5 mAh g-1 at 20.0 A g-1. Kinetic analysis of the prepared electrodes proved their ultrafast ionic and electronic conductivities. This strategy of hard templating reduces the number of routes required for preparing different types of electrodes, including NiO-based electrodes, and improves their electrochemical performance to enable their use in energy storage applications.
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Carbon nanofibers (CFs) have been widely applied as electrodes for energy storage devices owing to the features of increased contact area between electrodes and electrolyte, and shortened transmission route of electrons. However, the poor electrochemical activity and severe waste of space hinder their further application as supercapacitors electrodes. In this work, MnO2-x nanoflowers restricted and epitaxial growth in/out carbon nanofibers (MnO2/MnO@CF) were prepared as excellent electrode materials for supercapacitors. With the synergistic effect of uniquely designed structure and the introduction of MnO and MnO2 nanoflowers, the prepared interconnected MnO2/MnO@CF electrodes demonstrated satisfactory electrochemical performance. Furthermore, the MnO2/MnO@CF//activated carbon (AC) asymmetric supercapacitor offered an outstanding long-term cycle stability. Besides, kinetic analysis of MnO2/MnO@CF-90 was conducted and the diffusion-dominated storage mechanism was well-revealed. This concept of "internal and external simultaneous decoration" with different valence states of manganese oxides was proven to improve the electrochemical performance of carbon nanofibers, which could be generalized to the preparation and performance improvement of other fiber-based electrodes.
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With the wide application of electromagnetic waves in national defense, communication, navigation and home appliances, the electromagnetic pollution problem is becoming more and more prominent. Therefore, high-performance, and low-density composite wave-absorbing materials have attracted much attention. In this paper, three-dimensional (3D) network structures of flower-like 1T/2H Molybdenum disulfide nanosheets anchored to carbon fibers (1T/2H MoS2/CNFs) were prepared by electrostatic spinning technique and calcination process. The morphology and electromagnetic wave absorption properties were tuned by changing the content of flower-like MoS2. The optimized 1T/2H MoS2/CNFs composite exhibits superior electromagnetic wave absorption with minimum reflection (RLmin) of -42.26 dB and effective absorption bandwidth (EAB) of 6.48 GHz at 2.5 mm. Multi-facts contribute to the super performance. First, the uniquely designed nanosheet and 3D interconnected networks leads to multiple reflection and scattering of electromagnetic waves, which promotes the attenuation of electromagnetic waves. Second, the propriate content of CNFs and MoS2 with different phase regulates its impedance matching characteristic. Third, Numerous heterogeneous interfaces existed between CNFs and MoS2, 1T and 2H MoS2 phase results in interface polarization. Besides, the 1T/2H MoS2 rich in defects induces defect polarization, improving the dielectric loss. Furthermore, the electromagnetic wave absorption performance was proved via radar reflectance cross section simulation. This work illustrates 1T/2H MoS2/CNFs is a promising material for electromagnetic absorption with wide bandwidth, strong absorption, low density, and high thermal stability.
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Nickel cobaltate/NiCo-layered double hydroxides (NiCo2O4/NiCo-LDH) as energy storage materials offer considerable potential for various applications. However, many of current methods for synthesizing NiCo2O4/NiCo-LDH suffer from long synthesis times, complex preparation process, and high temperatures and high pressures. In this study, we present a green, simple, and efficient approach known as assisted liquid-phase plasma electrolysis, which realizes the rapid fabrication of ultra-fine NiCo2O4/NiCo-LDH nanoparticle-decorated electrospun carbon nanofibers (NiCo2O4/NiCo-LDH/CNFs) composites. Ultra-fine NiCo2O4/NiCo-LDH nanoparticles (<70 nm) are uniformly deposited on the CNF surface. The CNFs are intertwined to form a highly conductive three-dimensional mesh structure, which synergizes the NiCo2O4/NiCo-LDH nanoparticles with a high specific capacitance in favor of ion/electron transport efficiency. In addition, the cooperative effect between the two phases of NiCo2O4 and NiCo-LDH further improves the electrochemical properties. The NiCo2O4/NiCo-LDH/CNFs composites exhibit a high specific capacitance of 1534.7 F/g at 1 A/g and a capacitance retention of 93.9 % after 5000 cycles. An assembled asymmetric supercapacitor using activated carbon and NiCo2O4/NiCo-LDH/CNFs composites achieves an energy density of 33.8 Wh/kg at a power density of 400 W/kg and a capacitance retention of 93.0 % after 5000 cycles. Notably, two series-connected NiCo2O4/NiCo-LDH/CNFs ASC supercapacitors can light up an LED bulb, which maintains a certain brightness even after 50 min. Hence, this work provides a new and efficient route for synthesizing carbon-based NiCo2O4/NiCo-LDH composites for use as advanced energy storage materials.
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Salt mines are a special type of hypersaline environment. Current research mainly focuses on prokaryotes, and the understanding of viruses in salt mines remains limited. Understanding viruses in hypersaline environments is of great significance for revealing the formation and maintenance of microbial communities, energy flow and element cycling, and host ecological functions. A phage infecting Halomonas titanicae was isolated from Yipinglang Salt Mine in China, designated Halomonas titanicae phage vB_HtiS_YPHTV-1 (YPHTV-1). Transmission electron microscopy revealed that YPHTV-1 had an icosahedral head with a diameter of 49.12 ± 0.15 nm (n = 5) and a long noncontractile tail with a length of 141.7 ± 0.58 nm (n = 5), indicating that it was a siphovirus. The one-step growth curve showed that the burst size of YPHTV-1 was 69 plaque forming units (PFUs) cell-1. The genome of YPHTV-1 was 37,980 bp with a GC content of 36.2%. The phylogenetic analysis of the six conserved proteins indicated that YPHTV-1 formed a cluster with Bacillus phages and was separated from phages infecting Halomonas. The average nucleotide identity (ANI), phylogenetic, and network analyses indicated that the phage YPHTV-1 represented a new genus under Caudoviricetes. In total, 57 open reading frames (ORFs) were predicted in the YPHTV-1 genome, 30 of which could be annotated in the database. Notably, several auxiliary metabolic genes were encoded by YPHTV-1, such as ImmA/IrrE family metalloendopeptidase, mannose-binding lectin (MBL) folding metallohydrolase, M15 family of metal peptidases, MazG-like family protein, O antigen ligase, and acyltransferase. These genes potentially enabled the host bacterium to resist ionizing radiation, ultraviolet light (UV), mitomycin C, ß-lactam antibiotic, high osmotic pressure, and nutritional deficiencies. These findings highlight the role of haloviruses in the life cycle of halobacteria.
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Bacteriófagos , Genoma Viral , Análise de Sequência de DNA , Filogenia , Genômica , Myoviridae/genética , Fases de Leitura AbertaRESUMO
Objective.Sparse-view computed tomography (SVCT), which can reduce the radiation doses administered to patients and hasten data acquisition, has become an area of particular interest to researchers. Most existing deep learning-based image reconstruction methods are based on convolutional neural networks (CNNs). Due to the locality of convolution and continuous sampling operations, existing approaches cannot fully model global context feature dependencies, which makes the CNN-based approaches less efficient in modeling the computed tomography (CT) images with various structural information.Approach.To overcome the above challenges, this paper develops a novel multi-domain optimization network based on convolution and swin transformer (MDST). MDST uses swin transformer block as the main building block in both projection (residual) domain and image (residual) domain sub-networks, which models global and local features of the projections and reconstructed images. MDST consists of two modules for initial reconstruction and residual-assisted reconstruction, respectively. The sparse sinogram is first expanded in the initial reconstruction module with a projection domain sub-network. Then, the sparse-view artifacts are effectively suppressed by an image domain sub-network. Finally, the residual assisted reconstruction module to correct the inconsistency of the initial reconstruction, further preserving image details.Main results. Extensive experiments on CT lymph node datasets and real walnut datasets show that MDST can effectively alleviate the loss of fine details caused by information attenuation and improve the reconstruction quality of medical images.Significance.MDST network is robust and can effectively reconstruct images with different noise level projections. Different from the current prevalent CNN-based networks, MDST uses transformer as the main backbone, which proves the potential of transformer in SVCT reconstruction.