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1.
ACS Appl Mater Interfaces ; 16(9): 11421-11430, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38387026

RESUMEN

"High-capacity" graphite and "zero-strain" spinel Li4Ti5O12 (LTO) occupy the majority market of anode materials for Li+ storage in commercial applications. Nevertheless, their intrinsic drawbacks including the unsafe potential of graphite and unsatisfactory capacity of LTO limit the further development of lithium-ion batteries (LIBs), which is unable to satisfy the ever-increasing demands. Here, a novel Na0.35La0.55TiO3 perovskite embedded in multichannel carbon fibers (NLTO-NF) is rationally designed and synthesized through an electrospinning method. It not only has the advantages of a respectable specific capacity of 265 mAh g-1 at 0.1 A g-1 and superb rate capability, but it also possesses the zero-strain characteristic. Impressively, an ultralong cycling life with 96.3% capacity retention after 9000 cycles at 2 A g-1 is achieved in the half cell, and 90.3% of capacity retention ratio is obtained after even 2500 cycles at 1 A g-1 in the coupled LiFePO4/NLTO-NF full cell. This study introduces a new member with excellent performance to the zero-strain materials family for next-generation LIBs.

2.
Chem Commun (Camb) ; 59(66): 10000-10003, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37522160

RESUMEN

Layered V10O24·nH2O with a large interlayer spacing of 14 Å is hydrothermally synthesized and used as a cathode for potassium-ion batteries. It exhibits a capacity of 110 mA h g-1 with a capacity retention of 99.2% over 700 cycles. Its storage mechanism is identified as pseudo-capacitive intercalation.

3.
Materials (Basel) ; 16(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37297121

RESUMEN

Compared to Cr-Ni stainless steel, nickel-saving stainless steel is a low-cost austenitic stainless steel. We studied the deformation mechanism of stainless steel at various annealing temperatures (850 °C, 950 °C, and 1050 °C). The grain size of the specimen increases with increasing annealing temperature while the yield strength decreases, which follows the Hall-Petch equation. When plastic deformation occurs, dislocation increases. However, the deformation mechanisms can vary between different specimens. Stainless steel with smaller grains is more likely to transform into martensite when deformed. While twinning occurs when the grains are more prominent, the deformation results in twinning. The phase transformation during plastic deformation relies on the shear, so the orientation of the grains is relevant before and after plastic deformation.

4.
Nanoscale ; 14(42): 15640-15650, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36263768

RESUMEN

Among various cathode materials for sodium-ion batteries, Na3V2(PO4)3 has attracted much attention due to its outstanding electrochemical performance. However, the toxicity and expensive price of vanadium limit its practical application. Therefore, the substitution of vanadium with nontoxic and inexpensive transition metal elements is significant. We select the earth-abundant iron element to partially replace the vanadium element, and successfully synthesize Na3.36FeV(PO4)3 with a Na superionic conductor structure. Furthermore, a Na3.36FeV(PO4)3 cathode with an optimal carbon content can deliver an initial capacity of 97.6 mA h g-1 at 0.5C with a high capacity retention of 96.4% after 200 cycles. In addition, it also delivers an initial capacity of 90.4 mA h g-1 at 10C, and a capacity retention of 80% can be obtained after 5000 cycles. We also found that the lack of sodium in the material can be compensated by an electrochemical reaction. Furthermore, the in situ X-ray diffraction analysis reveals that the sodium storage process follows a pseudo-solid-solution reaction mechanism and the volume change ratio is less than 3% during charging/discharging. In order to study the practical application capability of Na3.36FeV(PO4)3, we assemble the pre-activated cathode and a hard carbon anode into a full cell, which exhibits high initial discharge capacities of 103 and 91.3 mA h g-1 at 0.5C and 10C, respectively. This work will provide new insights into the structural engineering of low-toxicity and ultralong-life NASICON-type cathode materials for SIBs.

5.
Entropy (Basel) ; 24(6)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35741567

RESUMEN

Semantic communication is a promising technology used to overcome the challenges of large bandwidth and power requirements caused by the data explosion. Semantic representation is an important issue in semantic communication. The knowledge graph, powered by deep learning, can improve the accuracy of semantic representation while removing semantic ambiguity. Therefore, we propose a semantic communication system based on the knowledge graph. Specifically, in our system, the transmitted sentences are converted into triplets by using the knowledge graph. Triplets can be viewed as basic semantic symbols for semantic extraction and restoration and can be sorted based on semantic importance. Moreover, the proposed communication system adaptively adjusts the transmitted contents according to channel quality and allocates more transmission resources to important triplets to enhance communication reliability. Simulation results show that the proposed system significantly enhances the reliability of the communication in the low signal-to-noise regime compared to the traditional schemes.

6.
Nanoscale ; 14(14): 5347-5355, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35343546

RESUMEN

Potassium-ion batteries (PIBs) are promising for large-scale energy storage due to the abundant reserves of the element potassium yet few satisfactory cathode materials have been developed due to the limitation of the large ionic radius of the potassium ion. Cubic perovskite fluorides have three-dimensional diffusion channels and a robust structure, which are favorable for ion transfer, but their poor electronic conductivity needs to be compensated. Here, we synthesized cubic KFeF3 powder by a solvothermal procedure. After the combination with reduced graphene oxide (rGO) and carbon coating, its electronic conductivity is greatly improved. In the optimal sample KFeF3/rGO-PVA-500, KFeF3 nano-particles (smaller than 50 nm) distribute on the rGO surface evenly. Owing to the special structure, KFeF3/rGO-PVA-500 provides an excellent rate performance and cycling stability. In particular, a high capacity retention of 94% is obtained after 1000 cycles at 200 mA g-1. In addition, a hybrid reaction mechanism combining mainly solid solution and partly conversion processes is revealed by employing in situ and ex situ characterization.

7.
J Mater Chem B ; 9(23): 4643-4653, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34009230

RESUMEN

Radiotherapy, as well as chemotherapy and surgery, occupies an essential position in tumor treatment. Nonetheless, insufficient radiation deposition and hypoxia-related radioresistance of cancer cells still are serious challenges in radiotherapy. Herein, we proposed a hollow PtCo nanosphere (PtCo NS)-based novel radiosensitizer with three advantages to sensitize tumor radiotherapy: (i) the high-Z element Pt ensured higher radiation absorption to cause more DNA damage, (ii) the platinum (Pt) and cobalt (Co) elements exhibited a dual catalase-like enzymatic activity to convert endogenic H2O2 to O2 efficiently, and (iii) the unique hollow nature of the PtCo NS provided a large specific surface area, which could amplify the catalytic reaction of H2O2 to induce reactive oxygen species and cancer cell apoptosis upon combination with radiation. Both in vivo and in vitro studies showed that the hollow PtCo NS could significantly inhibit tumor growth, simultaneously relieving tumor hypoxia with good biocompatibility and biosafety. This work presents a simple but multifunctional radiosensitizer with a unique hollow structure for radiotherapy enhancement.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Catalasa/metabolismo , Cobalto/química , Neoplasias Pulmonares/radioterapia , Nanopartículas del Metal/química , Nanosferas/química , Oxígeno/metabolismo , Platino (Metal)/química , Animales , Línea Celular Tumoral , Humanos , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Difracción de Polvo , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Aging (Albany NY) ; 12(5): 4603-4616, 2020 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-32165590

RESUMEN

Growing evidence highlighted the tumor mutational burden (TMB) as an important feature of carcinogenesis and therapeutic efficacy in esophageal cancer (EC). Our study aimed to explore the genomic landscape and the correlation between TMB and immune cell infiltration in EC patients with or without radiotherapy. The EC patients were categorized into high TMB (TMB-H) and low TMB (TMB-L) groups by the ESTIMATE algorithm, and subgroup analysis was performed based on receiving radiotherapy or not. Univariate regression analysis indicated TMB and TNM stages as high-risk prognostic factors (Hazard ratio > 1 and P < 0.05). Multivariate regression analysis suggested TMB as an independent prognostic factor (Hazard ratio = 1.051, P = 0.003). Kaplan-Meier analysis showed no significant difference of the overall survival (OS) between TMB-H and TMB-L groups (P = 0.082). However, EC patients without radiotherapy in the TMB-H group had significantly decreased OS (P = 0.038) and increased Tregs cell infiltration (P = 0.033). These results suggested TMB as a prognostic marker for EC patients. Especially for patients who did not receive radiotherapy, the prognosis of TMB-H patients was significantly poorer than that of TMB-L patients, which might result from the different regulatory T cell infiltration.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Mutación , Linfocitos T Reguladores/patología , Adenocarcinoma/patología , Adenocarcinoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/radioterapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Resultado del Tratamiento
9.
Ann Transl Med ; 7(12): 263, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31355230

RESUMEN

BACKGROUND: To systematically identity microRNA signatures, as well as miRNA-gene axes, for lung adenocarcinoma (LUAD) and to explore the potential biomarkers and mechanisms associated with the LUAD immune responses. METHODS: LUAD-related data were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), and these data were then used to identify the differentially expressed miRNAs that were downregulated in tumor tissues. Summary receiver operating characteristic curve analysis, survival analysis and meta-analysis were applied to evaluate the clinical significance and diagnostic value of the identified miRNAs. The presumed targets of the integrated-signature miRNAs were identified via 3 different target prediction algorithms: TargetScan, miRDB and DIANA-TarBase. Immunologic signature gene sets were enriched by gene set enrichment analysis (GSEA). Tumor-infiltrating lymphocytes were profiled by the Tumor IMmune Estimation Resource (TIMER). After pathway enrichment analysis using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases, pathway-gene networks were constructed using Cytoscape software. RESULTS: After integrated analysis of 4 GEO data sets (GSE48414, GSE51853, GSE63805 and GSE74190) and TCGA databases, miR-195 was identified as a potential clinical diagnostic marker. A total of 287 miR-195 target genes were screened, and 3 functional gene sets (GSE13485, GSE21379 and GSE29164) were enriched. GSE21379 was associated with the upregulation of CD4+ T cells in tumors, and the core genes were validated via the TIMER database. The CCDC88C expression level was significantly correlated with CD4+ T cell activation (partial.cor =0.437, P<0.001). Enrichment analysis revealed that CCDC88C was significantly enriched in the Wnt signaling pathway. CONCLUSIONS: MiR-195, as a suppressor of lung adenocarcinoma, regulates CD4+ T cell activation via CCDC88C.

10.
Oncotarget ; 8(39): 65642-65658, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-29029460

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a common malignant disease characterized by poor prognosis. Chemoresistance remains a major cause of ESCC relapse. Vaccinia-related kinase 1 (VRK1) has previously been identified as a cancer-related gene. However, there is little research demonstrating an association between VRK1 and ESCC. In this study, we show that VRK1 is overexpressed in ESCC primary tumor samples and cell lines. VRK1 expression was significantly correlated with clinical characteristics and predicted poor outcomes in ESCC patients. Functionally, knockdown of VRK1 inhibited ESCC cell proliferation, survival, migration and invasion; conversely, VRK1 overexpression produced the opposite effects. Furthermore, we found that up-regulation of VRK1 promoted cisplatin (CDDP) resistance in ESCC both in vitro and in vivo, whereas knockdown of VRK1 reduced this resistance. Further studies verified that VRK1 phosphorylated c-Jun and that the VRK1/c-Jun pathway contributed to CDDP resistance in ESCC. Mechanistically, a dual luciferase reporter assay revealed that c-Jun transcriptionally activated the expression of c-MYC. Silencing c-MYC abolished the c-Jun-mediated CDDP resistance of ESCC cells. A Kaplan-Meier analysis indicated that c-MYC is a potential prognostic factor in ESCC. Finally, luteolin, a VRK1 inhibitor, attenuated the malignant biological behaviors and CDDP resistance in ESCC cells. Collectively, we conclude that VRK1 promotes CDDP resistance through c-MYC by activating c-Jun and potentiating a malignant phenotype in ESCC. Our studies provide novel insight into the role of VRK1 in carcinogenesis and indicate that VRK1 can serve as a potential therapeutic target in ESCC.

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