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1.
ACS Nano ; 17(20): 20621-20633, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37791899

RESUMO

Nickel-rich LiNi0.8Co0.15Al0.015O2 (NCA) with excellent energy density is considered one of the most promising cathodes for lithium-ion batteries. Nevertheless, the stress concentration caused by Li+/Ni2+ mixing and oxygen vacancies leads to the structural collapse and obvious capacity degradation of NCA. Herein, a facile codoping of anion (F-)-cation (Mg2+) strategy is proposed to address these problems. Benefiting from the synergistic effect of F- and Mg2+, the codoped material exhibits alleviated Li+/Ni2+ mixing and demonstrates enhanced electrochemical performance at high voltage (≥4.5 V), outperformed the pristine and F-/Mg2+ single-doped counterparts. Combined experimental and theoretical studies reveal that Mg2+ and F- codoping decreases the Li+ diffusion energy barrier and enhances the Li+ transport kinetics. In particular, the codoping synergistically suppresses the Li+/Ni2+ mixing and lattice oxygen escape, and alleviates the stress-strain accumulation, thereby inhibiting crack propagation and improving the electrochemical performance of the NCA. As a consequence, the designed Li0.99Mg0.01Ni0.8Co0.15Al0.05O0.98F0.02 (Mg1+F2) demonstrates a much higher capacity retention of 82.65% than NCA (55.69%) even after 200 cycles at 2.8-4.5 V under 1 C. Furthermore, the capacity retention rate of the Mg1+F2||graphite pouch cell after 500 cycles is 89.6% compared to that of the NCA (only 79.4%).

2.
Biomimetics (Basel) ; 8(5)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37754147

RESUMO

The slime mold algorithm (SMA) and the arithmetic optimization algorithm (AOA) are two novel meta-heuristic optimization algorithms. Among them, the slime mold algorithm has a strong global search ability. Still, the oscillation effect in the later iteration stage is weak, making it difficult to find the optimal position in complex functions. The arithmetic optimization algorithm utilizes multiplication and division operators for position updates, which have strong randomness and good convergence ability. For the above, this paper integrates the two algorithms and adds a random central solution strategy, a mutation strategy, and a restart strategy. A hybrid slime mold and arithmetic optimization algorithm with random center learning and restart mutation (RCLSMAOA) is proposed. The improved algorithm retains the position update formula of the slime mold algorithm in the global exploration section. It replaces the convergence stage of the slime mold algorithm with the multiplication and division algorithm in the local exploitation stage. At the same time, the stochastic center learning strategy is adopted to improve the global search efficiency and the diversity of the algorithm population. In addition, the restart strategy and mutation strategy are also used to improve the convergence accuracy of the algorithm and enhance the later optimization ability. In comparison experiments, different kinds of test functions are used to test the specific performance of the improvement algorithm. We determine the final performance of the algorithm by analyzing experimental data and convergence images, using the Wilcoxon rank sum test and Friedman test. The experimental results show that the improvement algorithm, which combines the slime mold algorithm and arithmetic optimization algorithm, is effective. Finally, the specific performance of the improvement algorithm on practical engineering problems was evaluated.

3.
Sci Rep ; 13(1): 7983, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198226

RESUMO

In this work, an ultrathin acoustic metamaterial formed by space-coiled water channels with a rubber coating is proposed for underwater sound absorption. The proposed metamaterial achieves perfect sound absorption ([Formula: see text] > 0.99) at 181 Hz, which has a deep subwavelength thickness ([Formula: see text]). The theoretical prediction is consistent with the numerical simulation, which demonstrate the broadband low-frequency sound absorption performance of the proposed super absorber. The introduction of rubber coating leads to a significant decrease of the effective sound speed in the water channel, resulting in the phenomenon of slow-sound propagation. From the perspective of numerical simulations and acoustic impedance analysis, it is proved that the rubber coating on the channel boundary causes slow-sound propagation with inherent dissipation, which is the key to meet the impedance matching condition and achieve perfect low-frequency sound absorption. Parametric studies are also carried out to investigate the effect of specific structural and material parameters on sound absorption. By tailoring key geometric parameters, an ultra-broadband underwater sound absorber is constructed, with a perfect absorption range of 365-900 Hz and a deep subwavelength thickness of 33 mm. This work paves a new way for designing underwater acoustic metamaterials and controlling underwater acoustic waves.

4.
J Gastrointest Oncol ; 14(2): 744-757, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37201067

RESUMO

Background: Despite advances in colon cancer screening, diagnosis, chemotherapy, and targeted therapy, the prognosis remains poor once colon cancer develops distant metastasis or local recurrence. To further improve the prognosis of colon cancer patients, researchers or clinicians may need to identify new indicators for predicting the prognosis and treatment of colon cancer. Methods: In order to discover the new mechanism of epithelial-mesenchymal transition (EMT) promoting tumor progression and to find new indicators of colon cancer diagnosis, targeted therapy and prognosis, this study conducted The Cancer Genome Atlas (TCGA) analysis, differential gene analysis, prognostic analysis, protein-protein interaction (PPI), enrichment analysis, molecular typing, and a machine algorithm were combined with data from TCGA and Gene Expression Omnibus (GEO) databases and EMT-related genes. Results: Our study identified 22 EMT-related genes with clinical prognostic value in colon cancer. On the basis of 22 EMT-related genes, we divided colon cancer into 2 different molecular subtypes by non-negative matrix factorization (NMF) model using 14 differentially expressed genes (DEGs), and the DEGs were enriched in multiple signaling pathways related to tumor metastasis process. Further analysis of EMT DEGs revealed that the PCOLCE2 and CXCL1 genes were characteristic genes for clinical prognosis of colon cancer. Conclusions: In this study, 22 prognostic genes were screened out from 200 EMT-related genes, and then the PCOLCE2 and CXCL1 molecules were finally focused on through the combination of the NMF molecular typing model and machine learning screening feature genes, suggesting that PCOLCE2 and CXCL1 may have good application potential. The findings provide a theoretical basis for the next clinical transformation in the treatment of colon cancer.

5.
Bioengineered ; 13(3): 5928-5941, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35192430

RESUMO

Shikonin (SHK), a major component of shiverweed, was provided with anti-tumor effects via multiple targets and signal pathways. Nevertheless, the specific mechanism of its function in colorectal cancer (CRC) still needed to be further explored. The study was designed to examine the role of SHK in CRC and its specific mechanism on the cell tumor behavior of CRC. Collection of clinical samples was performed, and test of microRNA (miR)-545-3p and guanine nucleotide-binding protein beta polypeptide 1 (GNB1) in the samples was conducted; Selection of CRC cell line was exerted, and examination of miR-545-3p and GNB1 was performed; After treatment of shikonin (SHK), correlated plasmids were transfected, test of cell advancement was performed. Test of the protein of autophagy-correlated proteins light chain 3-II/light chain 3I and p63 was performed. The interaction of miR-545-3p with GNB1 was explored, and the action of SHK in vivo was tested. SHK repressed the advancement of SW480 cells with elevated apoptosis and autophagy and the cells quantities in G0/G1 phase. MiR-545-3p was elevated in CRC. SHK boosted miR-545-3p, repression of miR-545-3p or augmentation of GNB1 was able to turn around the function of SHK on CRC, and GNB1 was the target gene of miR-545-3p.All in all, SHK stimulates apoptosis and autophagy in CRC via miR-545-3p/GNB1 signaling axis, firstly demonstrating the regulatory mechanism of SHK in CRC via miR-545-3p/GNB1 axis.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Subunidades beta da Proteína de Ligação ao GTP , MicroRNAs , Autofagia/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias do Colo/genética , Neoplasias Colorretais/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Naftoquinonas
6.
J Biomech ; 101: 109617, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31959390

RESUMO

Although arterial blood flow is physiologically non-periodic under resting conditions, periodic flow assumption has been widely adopted in most hemodynamic studies. So far, it remains unclear how the non-periodicity of blood flow would influence local hemodynamic parameters, especially wall shear stress (WSS) that associates closely with endothelial function and vascular disease. In this study, numerical simulations of blood flows in sixteen normal carotid artery bifurcations were performed under measured non-periodic and averaged periodic flow conditions, respectively, with the obtained results being compared in terms of five typical WSS metrics (i.e., mean WSS (MWSS), time-averaged WSS (TAWSS), oscillatory shear index (OSI), transverse WSS (transWSS), and average temporal gradient of WSS (WSSTG)) in the atheroprone low-WSS regions. It was found that simplifying the physiologically non-periodic flow condition into a periodic one did not significantly alter the major features of WSS distribution, but resulted in underestimations of some WSS metrics. Specifically, the degree of underestimation was largest (27.2% ± 8.3%) for WSSTG, smallest (0.5% ± 0.4%) for MWSS, while moderate (5.1% ± 3.2% ~ 9.2% ± 4.1%) for other WSS metrics. Statistical analyses revealed that the cycle-to-cycle variability of flow velocity waveform (var-V) and the planarity of internal carotid artery correlated strongly with the periodic flow assumption-induced underestimations of WSS metrics. These findings suggest that taking the non-periodic characteristic of blood flow into consideration could be important for studying hemodynamics in arteries with a large var-V or specific morphological characteristics, especially when WSSTG is the main hemodynamic parameter of concern.


Assuntos
Artérias Carótidas/fisiologia , Modelos Cardiovasculares , Resistência ao Cisalhamento , Estresse Mecânico , Velocidade do Fluxo Sanguíneo , Hemodinâmica , Humanos , Masculino
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