16 research outputs found

    Properties of single-layer graphene doped by nitrogen with different concentrations

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    Graphene has vast promising applications on the nanoelectronics and spintronics because of its unique magnetic and electronic properties. Making use of an ab initio spin-polarized density functional theory, implemented by the method of Heyd-Scuseria-Ernzerhof 06(HSE06) hybrid functional, the properties of nitrogen substitutional dopants in semi-metal monolayer graphene were investigated. We found from our calculation, that introducing nitrogen doping would possibly break energy degeneracy with respect to spin(spin symmetry breaking) at some doping concentrations with proper dopant configurations. The spin symmetry breaking would cause spin-polarized effects, which induce magnetic response in graphene. This paper systematically analyzed the dependence of magnetic moments and band gaps in graphene on doping concentrations of nitrogen atoms, as well as dopant configurations.Comment: 17pages,4figures,5table

    Unified description of perturbation theory and band center anomaly in one-dimensional Anderson localization

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    We calculated numerically the localization length of one-dimensional Anderson model with diagonal disorder. For weak disorder, we showed that the localization length changes continuously as the energy changes from the band center to the boundary of the anomalous region near the band edge. We found that all the localization lengths for different disorder strengths and different energies collapse onto a single curve, which can be fitted by a simple equation. Thus the description of the perturbation theory and the band center anomaly were unified into this equation.Comment: 10 pages, 6 figure

    Size-dependent melting: Numerical calculations of the phonon spectrum

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    In order to clarify the relationship between the phonon spectra of nanoparticles and their melting temperature, we studied in detail the size-dependent low energy vibration modes. A minimum model with atoms on a lattice and harmonic potentials for neighboring atoms is used to reveal a general behavior. By calculating the phonon spectra for a series of nanoparticles of two lattice types in different sizes, we found that density of low energy modes increases as the size of nanoparticles decreases, and this density increasing causes decreasing of melting temperature. Size-dependent behavior of the phonon spectra accounts for typical properties of surface-premelting and irregular melting temperature on fine scales. These results show that our minimum model captures main physics of nanoparticles. Therefore, more physical characteristics for nanoparticles of certain types can be given by phonons and microscopic potential models.Comment: 5 pages, 5 figure

    Apolipoprotein C1 promotes tumor progression in gastric cancer

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    BACKGROUND: Gastric cancer (GC) is a malignancy with the worst prognosis that seriously threatens human health, especially in East Asia. Apolipoprotein C1 (apoc1) belongs to the apolipoprotein family. In addition, apoc1 has been associated with various tumors. However, its role in GC remains unclear. Methods: Firstly, we quantified its expression in GC and adjacent tumor tissues, using The Cancer Genome Atlas (TCGA). Next, we assessed cell invasion and migration abilities. Finally, we revealed the role of apoc1 in the tumor microenvironment (TME), immune cell infiltration and drug sensitivity. Results: Firstly, in TCGA database, it has been shown that elevated expression of apoc1 was identified in various cancers, including GC, then we found that high expression of apoc1 was significantly correlated with poor prognosis in GC. Histologically, apoc1 expression is proportional to grade, cancer stage, and T stage. The experimental results showed that apoc1 promoted cell invasion and migration. Then GO, KEGG, and GSEA pathway analyses indicated that apoc1 may be involved in the WNT pathway and immune regulation. Furthermore, we found out the tumor-infiltrating immune cells related to apoc1 in the tumor microenvironment (TME) using TIMER. Finally, we investigated the correlation between apoc1 expression and drug sensitivity, PD-1 and CTLA-4 therapy. Conclusions: These results suggest that apoc1 participates in the evolution of GC, and may represent a potential target for detection and immunotherapy in GC

    Biomimetic Water-Collecting Fabric with Light-Induced Superhydrophilic Bumps

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    To develop an efficient water-collecting surface that integrates both fast water-capturing and easy drainage properties is of high current interest for addressing global water issues. In this work, a superhydrophobic surface was fabricated on cotton fabric via manipulation of both the surface roughness and surface energy. This was followed by a subsequent spray coating of TiO<sub>2</sub> nanosol that created light-induced superhydrophilic bumps with a unique raised structure as a result of the interfacial tension of the TiO<sub>2</sub> nanosol sprayed on the superhydrophobic fiber surface. These raised TiO<sub>2</sub> bumps induce both a wettability gradient and a shape gradient, synergistically accelerating water coalescence and water collection. The in-depth study revealed that the quantity and the distribution of the TiO<sub>2</sub> had a significant impact on the final water collection efficiency. This inexpensive and facilely fabricated fabric biomimicks the desert beetleā€™s back and spider silk, which are capable of fog harvesting without additional energy consumption

    CPXM1 correlates to poor prognosis and immune cell infiltration in gastric cancer

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    Background: Gastric cancer (GC) is the fourth most common cause of cancer-related death and the fifth most frequent malignant cancer, especially advanced GC. Carboxypeptidase X member 1 (CPXM1) is an epigenetic factor involved in many physiological processes, including osteoclast differentiation and adipogenesis. Several studies have shown the association of CPXM1 with multiple tumors; however, the mechanism of CPXM1 involvement in the progression of GC is yet to be characterized. Method: CPXM1 expression data were obtained from the Tumor Immune Estimation Resource. The Cancer Genome Atlas and the Gene Expression Omnibus databases were used to obtain patient-matched clinicopathological information, and the Kaplanā€“Meier plot database was utilized for the prognosis analysis of GC patients. The Catalog of Somatic Mutations in Cancer and cBioportal databases were adopted to study CPXM1 mutations in tumors. Next, we utilized the Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Gene Set Enrichment Analysis for mechanism research. Furthermore, we performed tumor microenvironment and immune infiltration analysis based on CPXM1. Finally, we predicted sensitivity to several targeted drugs in GC patients based on CPXM1.CPXM1 is upregulated in GC and is correlated with poor prognosis, gender, and tumor stage in GC patients. Gene enrichment analysis suggested that CPXM1 may regulate the occurrence and progression of GC via the PI3Kā€“AKT and TGF-Ī² pathway. Moreover, CPXM1 expression results in an increase in the proportion of immune and stromal cells. Additionally, the proportion of plasma cells was inversely related to the expression of CPXM1, whereas macrophage M2 expression was proportionate to CPXM1 expression. Finally, six small-molecule drugs that showed notable variations in IC50 between two groups were screened. Conclusion: These results suggested that CPXM1 regulates the progression of GC and may represent a novel target for the detection and treatment of GC
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