Layered double hydroxide (LDH) is potentially excellent supercapacitor (SC) materials, but the low conductivity and easy agglomeration limit the further improvement of their electrochemical ...properties. Therefore, LDHs are requisite to grow on some conductive substrates to produce high-performance SC. In this paper, the conductive two-dimensional (2D) transition metal carbides, nitrides and carbonitrides (called MXene) were explored as the substrate to directly deposit NiFe-LDH nanosheets by a one-step hydrothermal method, then a three-dimensional (3D) porous NiFe-LDH/MXene electrode was obtained. The morphology and electrochemical performance of the composite electrodes were analyzed and investigated. The results show that the NiFe-LDH/MXene electrode has larger specific capacitance (720.2 F/g) than NiFe-LDH (465 F/g), and the capacitance of the composite electrode retained 86% after 1000 cycles (only 24% for NiFe-LDH), showing excellent cycle stability. The improved electrochemical performance of the composites is caused by the stable sheet-like structure of NiFe-LDH during charge-discharge time and the conductive network formed by the MXene, which can accelerates electron transport. In addition, the asymmetric SC based on NiFe-LDH/MXene positive electrode display a power density of 758.27 W/kg at an energy density of 42.4 Wh/Kg. These results indicate the NiFe-LDH/MXene composites can be applied as the novel candidate of high-performance SC electrodes.
•The LDH/MXene synergistic hybrid structure is developed with MXene nanosheets as the substrate.•Prominent electrical performance is attributed to MXene providing a fast charge transfer path for LDH.•The anchoring of LDH on MXene surface provides the material with enhanced cyclic stability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, Nickel–Cobalt layered double hydroxide (NiCo-LDH) nanosheets were first in situ synthesized on MXene (Ti3C2) via a simple hydrothermal method, then glucose sensing performance based on ...three-dimensional porous MXene/NiCo-LDH nanocomposite was explored. At a working potential of 0.45 V (vs. SCE), the glucose sensor exhibits a wide linearity range (0.002 mM–4.096 mM), a low limit of detection (0.53 μM) and a rapid response (<3 s). Moreover, good selectivity, reproducibility and stability were also obtained. And the excellent performance can attribute to large area of contact of materials surface with glucose, fast electron transfer rate and easy diffusion of electrolyte provided by the novel 3D porous NiCo-LDH nanosheets on the conductive MXene substrate. Therefore, MXene/NiCo-LDH composites will be a candidate for electrochemical detection of glucose.
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•NiCo-LDH nanosheets with high specific surface area grew on the surface of MXene and formed 3D porous structure.•The oxidation performance towards glucose between MXene/NiCo-LDH and NiCo-LDH was compared.•The MXene/NiCo-LDH/GCE was used for detection of glucose and the limit of detection is 0.53 μM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The supercapacitor (SC) based on nickel cobalt layered double hydroxide (NiCo-LDH) has aroused great interest in the field of energy storage. However, the agglomeration and low electrical ...conductivity are unfavorable for electrochemical performance. Herein, Ag nanowires (Ag NWs) was first dip-coated on nickel foam (NF) to form a conductive substrate, on which the NiCo-LDH nanosheet array in-situ grew to construct an efficient three-dimensional (3D) self-supported hierarchical structure NiCo-LDH/Ag NWs/NF electrode. The presence of Ag NWs inhibits aggregation of LDH nanosheets and accelerates the electron transfer. Electrochemical studies exhibit that NiCo-LDH/Ag/NF hybrid electrode possesses the higher specific capacitance of 2920.6 F g−1 at a current density of 5 A g−1 and excellent cycling stability (89.8% after 2000 cycles) compared with the electrode without Ag NWs. The asymmetric supercapacitor (ASC) with the NiCo-LDH/Ag/NF heterostructure as the positive electrode and active carbon (AC) as the negative electrode displays a high energy density of 42.9 Wh kg−1 at a power density of 800 W kg−1. When two aqueous ASCs were assembled in series and charged for only 1 min, the stored energy was capable of powering two green light-emitting-diodes (LEDs) for more than 3 min, indicating NiCo-LDH/Ag/NF electrode material shows great potential application in supercapacitor.
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•Ag NWs and 3D ultrathin NiCo-LDH nanosheets are successively decorated on Ni foam.•The conductivity and active sites of electrode are enhanced by the addition of Ag NWs.•The specific capacitance of NiCo-LDH/Ag/NF electrode is 2920.6 F g−1 at 5 A g−1.•The assembled asymmetric supercapacitor exhibits high energy and power densities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The common and divergent genetic mechanisms of hyperandrogen (HA) and normoandrogen (NA) polycystic ovary syndrome (PCOS) are currently unknown.
This study aimed to explore the hub genes and ...potential mechanisms of HA and NA PCOS through bioinformatics analysis.
The GSE137684 dataset was downloaded from the Gene Expression Omnibus (GEO) database. The co-expressed genes and differentially expressed genes (DEGs) between HA and NA PCOS samples were functionally annotated by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The protein-protein interaction (PPI) network of the DEGs was constructed and visualized using STRING and Cytoscape, respectively, and the hub genes were screened using the Cytohubba plug-in. The transcription factors (TFs) of these hub genes were identified with the JASPAR database, and the hub gene-TF regulatory network was constructed.
A total of 327 DEGs, including 191 upregulated and 136 downregulated genes, were identified in HA PCOS relative to NA PCOS. Ten hub genes were screened, of which MYC, CAV1, and HGF were mainly enriched in the Proteoglycans in the cancer pathway. In addition, 47 TFs were identified that were found to be involved in the regulation of hub genes.
MYC, CAV1, and HGF are potential diagnostic biomarkers and therapeutic targets for HA PCOS.
We report the atmospheric pressure chemical vapor deposition (CVD) growth of single-layer graphene over a crystalline Cu(1
1
1) film heteroepitaxially deposited on
c-plane sapphire. ...Orientation-controlled, epitaxial single-layer graphene is achieved over the Cu(1
1
1) film on sapphire, while a polycrystalline Cu film deposited on a Si wafer gives non-uniform graphene with multi-layer flakes. Moreover, the CVD temperature is found to affect the quality and orientation of graphene grown on the Cu/sapphire substrates. The CVD growth at 1000
°C gives high-quality epitaxial single-layer graphene whose orientation of hexagonal lattice matches with the Cu(1
1
1) lattice which is determined by the sapphire’s crystallographic direction. At lower CVD temperature of 900
°C, low-quality graphene with enhanced Raman D band is obtained, and it showed two different orientations of the hexagonal lattice; one matches with the Cu lattice and another rotated by 30°. Carbon isotope-labeling experiment indicates rapid exchange of the surface-adsorbed and gas-supplied carbon atoms at the higher temperature, resulting in the highly crystallized graphene with energetically most stable orientation consistent with the underlying Cu(1
1
1) lattice.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Epitaxial chemical vapor deposition (CVD) growth of uniform single-layer graphene is demonstrated over Co film crystallized on c-plane sapphire. The single crystalline Co film is realized on the ...sapphire substrate by optimized high-temperature sputtering and successive H2 annealing. This crystalline Co film enables the formation of uniform single-layer graphene, while a polycrystalline Co film deposited on a SiO2/Si substrate gives a number of graphene flakes with various thicknesses. Moreover, an epitaxial relationship between the as-grown graphene and Co lattice is observed when synthesis occurs at 1000 °C; the direction of the hexagonal lattice of the single-layer graphene completely matches with that of the underneath Co/sapphire substrate. The orientation of graphene depends on the growth temperature and, at 900 °C, the graphene lattice is rotated at 22 ± 8° with respect to the Co lattice direction. Our work expands a possibility of synthesizing single-layer graphene over various metal catalysts. Moreover, our CVD growth gives a graphene film with predefined orientation, and thus can be applied to graphene engineering, such as cutting along a specific crystallographic direction, for future electronics applications.
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IJS, KILJ, NUK, PNG, UL, UM
Size, orientation, and boundary of graphene domains are the current focus of chemical vapor deposition (CVD) growth because they are closely related to graphene’s physical properties. Here, we study ...the domain structure of single-layer graphene grown by ambient pressure CVD over heteroepitaxial Cu(111) and Cu(100) films. Low energy electron microscope measurements reveal that the Cu(111) film gives uniform single-layer graphene whose orientation is consistent with the underlying Cu lattice for areas over 1 mm2. On the other hand, single-layer graphene grown on Cu(100) film exhibits clear multidomain structure with two main orientations rotated by 30°. Moreover, a weak Raman D-band is observed along the domain boundaries for the graphene grown on the Cu(100). Our results give new insights into the growth mechanism of CVD-grown graphene over Cu metals and offer a new direction for the realization of single-crystalline graphene.
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IJS, KILJ, NUK, PNG, UL, UM
The synthesis of large area, homogenous, single layer graphene on cobalt （Co） and nickel （Ni） is reported. The process involves vacuum annealing of sputtered amorphous carbon （a-C） deposited on ...Co/sapphire or Ni/sapphire substrates. The improved crystallinity of the metal film, assisted by the sapphire substrate, proves to be the key to the quality of as-grown graphene film. The crystallinity of the Co and Ni metal films was improved by sputtering the metal at elevated temperature as was verified by X-ray diffraction （XRD）. After sputtering of a-C and annealing, large area, single layer graphene that occupies almost the entire area of the substrate was produced. With this method, 100 mm2-area single layer graphene can be synthesized and is limited only by the substrate and vacuum chamber size. The homogeneity of the graphene film is not dependent on the cooling rate, in contrast to syntheses using polycrystalline metal films and conventional chemical vapor deposition （CVD） growth. Our facile method of producing single layer graphene on Co and Ni metal films should lead to large scale graphene-based applications.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The omission of axillary lymph node dissection (ALND) or axillary radiation (AxRT) remains controversial in patients with clinical node-negative early breast cancer and a positive sentinel lymph ...node.
We conducted a comprehensive review by searching PubMed, Embase, Web of Science, and Cochrane databases (up to November 2023). Our primary outcomes were overall survival (OS), disease-free survival (DFS), locoregional recurrence (LRR), and axillary recurrence (AR).
We included 26 studies encompassing 145,548 women with clinical node-negative early breast cancer and positive sentinel lymph node. Pooled data revealed no significant differences between ALND and sentinel lymph node biopsy (SLNB) alone in terms of OS (hazard ratio HR0.99, 95% confidence interval CI 0.91-1.08,
=0.84), DFS (HR 1.04, 95% CI 0.90-1.19,
=0.61), LRR (HR 0.76, 95% CI 0.45-1.20,
=0.31), and AR (HR 1.01, 95% CI 0.99-1.03,
=0.35). Similarly, no significant differences were observed between AxRT and SLNB alone for OS (HR 0.57, 95% CI 0.32-1.02,
=0.06) and DFS (HR 0.52, 95% CI 0.26-1.05,
=0.07). When comparing AxRT and ALND, a trend towards higher OS was observed the AxRT group (HR 0.08, 95% CI 0.67-1.15), but the difference did not reach statistical significance (
=0.35, I
= 0%). Additionally, no significant differences significance observed for DFS or AR (
=0.13 and
=0.73, respectively) between the AxRT and ALND groups.
Our findings suggest that survival and recurrence rates are not inferior in patients with clinical node-negative early breast cancer and a positive sentinel lymph node who receive SLNB alone compared to those undergoing ALND or AxRT.
Thoracic paravertebral schwannoma is originated in Schwann cells that encompass the peripheral nerve fibers. Although conventional thoracotomy or thoracoscopic surgical strategy is identified as ...standard technique for the resection, we herein report a case of a thoracic paravertebral benign schwannoma successfully treated with full-endoscopic technique.
A 47-year-old female was found a lesion in the right posterior mediastinum when she received a chest CT two weeks prior. The patient presented with no symptoms. She underwent posterior endoscopic resection of the lesion. To our knowledge, this is the first case of full endoscopic surgical treatment to deal with a thoracic paravertebral schwannoma pronounced to date.
Considering the dimension of the tumor and its surroundings, we performed gross-total resection through endoscopic approach. This technique was safe and effective in this patient.
Full endoscopic resection is suitable for thoracic paravertebral schwannoma in certain populations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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