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Clever and rational design of structural hierarchy, along with precise component adjustment, holds profound significance for the construction of high-performance supercapacitor electrode materials. In this study, a binder-free self-supported CCO@N0.5 C0.5 OH/NF cathode material is constructed with hierarchical hetero-core-shell honeycomb nanostructure by first growing CuCo2 O4 (CCO) nanopin arrays uniformly on highly conductive nickel foam (NF) substrate, and then anchoring Ni0.5 Co0.5 (OH)2 (N0.5 C0.5 OH) bimetallic hydroxide nanosheet arrays on the CCO nanopin arrays by adjusting the molar ratio of Ni(OH)2 and Co(OH)2 . The constructed CCO@N0.5 C0.5 OH/NF electrode material showcases a wealth of multivalent metal ions and mesopores, along with good electrical conductivity, excellent electrochemical reaction rates, and robust long-term performance (capacitance retention rate of 87.2%). The CCO@N0.5 C0.5 OH/NF electrode, benefiting from the hierarchical structure of the material and the exceptional synergy between multiple components, demonstrates an excellent specific capacitance (2553.6 F g-1 at 1 A g-1 ). Furthermore, the assembled asymmetric CCO@N0.5 C0.5 OH/NF//AC/NF supercapacitor demonstrates a high energy density (70.1 Wh kg-1 at 850 W kg-1 ), and maintains robust capacitance cycling stability performance (83.7%) after undergoing 10 000 successive charges and discharges. It is noteworthy that the assembled supercapacitor exhibits an operating voltage (1.7 V) that is well above the theoretical value (1.5 V).
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Flexible energy storage device is one of the most critical components as power source for wearable electronics. The emergence of MXenes, a growing family of 2D nanomaterials, has demonstrated a brand-new possibility for flexible energy storage. However, the fabrication of MXene films with satisfactory mechanical, electrical, and electrochemical reliabilities remains challenging due to the weak interlayer interactions and self-restacking of MXene sheets. Sequential bridging of polydopamine/polyethyleneimine-functionalized (PDA/PEI)-coated MXene sheets to induce synergistically covalent and hydrogen binding connections of MXene-based films is demonstrated here. By interrupting self-hydrogen bonding and π-π stacking interactions, the introduction of long-chain PEI can not only inhibit the massive aggregation of PDA, but also improve the continuity of the interconnection network of PDA/PEI between MXene layers. Hence, the as-prepared MXene/PDA/PEI composite film displays high mechanical strength (≈366 MPa) which achieves 12-fold improvement compared with pure MXene film, as well as superior energy storage capability (≈454 F g-1 at 5 mV s-1 ) and rate performance of ≈48% at 10 000 mV s-1 . This modulation of inserted polymer between MXene layers can provide an avenue for assembling high performance MXene films, and can even be extended to the fabrication of other 2D platelets for varied applications.
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Due to the existence of the aerosol, the traditional method of measuring atmospheric temperature by using Rayleigh scattering technique has limitations in the low altitude. A pure rotational Raman lidar to get tropospheric temperature profiles is built. We carried out the atmospheric temperature observation in Beijing for two months. The atmospheric temperature profile was retrieved using the observed rotational Raman scattering signals. The effect of smooth window, calibration range and calibration constant on the retrieval precision of the atmospheric temperature was evaluated and analyzed. The results show that with the increase of smooth window, the mean absolute deviation between the lidar and radiosonde firstly decreases and then increases; in order to remove effectively the effect of random error in the return signals, while maintaining the fine vertical structure of temperature profile, it is better to choose the range between 600 and 1 200 m for smooth window. When calibration range is different, the mean absolute deviation between the lidar and radiosonde is varied, the relative variation of the deviation is about 0.07 K. When both calibration constant a and b increase or decrease, the mean deviation between the lidar and radiosonde increases; when one increases and another decreases, the mean deviation has a tendency to cancel each other out. The variance probability of a or b is not equal, and the variance of a and b is always contrary in the sign; the mean deviation is not sensitive to variance of a or b, and it is sensitive to the whole variance of a and b, about 91.7% of the mean deviation is in the range between -3 and 3 K. These results provide the theoretical basis for the selection of smooth window and calibration range in pure rotational Raman lidar data retrieval, and the reference for the error of actual temperature inversion result caused by lidar calibration constant.
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The selection of highly efficient materials and the construction of advantageous structures are essential for realizing high-performance electrode materials. In this paper, electrode material Cu2S/C@NiMnCe-LDH/CF with excellent morphology and high performance has been successfully designed and prepared by simple hydrothermal and calcination techniques. First, ZIF-67 is loaded on the outer layer of Cu2S rods to obtain core-shell structured Cu2S@ZIF-67 rods, whose ZIF-67 MOF shell is carbonized to obtain Cu2S@C rods. Then, NiMnCe-LDH are epitaxially loaded on the outer layer of Cu2S@C to obtain Cu2S/C@NiMnCe-LDH rods. At a current density of 2 mA cm-2, Cu2S/C@NiMnCe-LDH/CF exhibits an area capacitance of 5176.4 mF cm-2. The mass capacitance and the energy density of the Cu2S/C@NiMnCe-LDH/CF//AC asymmetric supercapacitor (ASC) reach 150.82F g-1 at a sweep rate of 0.8 A/g and 53.62 Wh kg-1 at a power density of 639.99 W kg-1, respectively. Meanwhile, after 8000 electrochemical cycles, the specific capacitance of Cu2S/C@NiMnCe-LDH/CF//AC still has a retention rate of 86.32 %, which proves its excellent cycling stability. These results demonstrate a new strategy for the preparation of novel core-shell structured Cu2S/C@NiMnCe-LDH/CF nanocomposite material for electrode materials of energy storage devices with superb performance.
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Stretchable flexible thin-film electrodes are extensively explored for developing new wearable energy storage devices. However, traditional carbon-based materials used in such independent electrodes have limited practical applications owing to their low energy storage capacity and energy density. To address this, a unique structure and remarkable mechanical stability thin-film flexible positive electrode comprising CoS1.97 nanoparticles decorated hollow CuS cubes and reduced graphene oxide (rGO), hereinafter referred to as CCSrGO, is prepared. Transition metal sulfide CoS1.97 and CuS shows high energy density owing to the synergistic effects of its active components. The electrode can simultaneously meet the high-energy density and safety requirements of new wearable energy storage devices. The electrode has excellent electrochemical performance (1380 F/g at 1 A/g) and ideal capacitance retention (93.8 % after 10,000 cycles) owing to its unique three-dimensional hollow structure and polymetallic synergies between copper and cobalt elements, which are attributed to their different energy storage mechanisms. Furthermore, a flexible asymmetric supercapacitor (FASC) was constructed using CCSrGO as the positive electrode and rGO as the negative electrode (CCSrGO//rGO), which delivers an energy density of 100 Wh kg-1 and a corresponding power density of 2663 W kg-1 within a voltage window of 0-1.5 V. The resulting FASC can power a light-emitting diode (LED) at different bending and twisting angles, exerting little effect on the capacitance. Therefore, the prepared CCSrGO//rGO FASC devices show great application prospects in energy storage.
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Compression-tolerant electrodes are critical for developing next-generation wearable energy storage devices. However, most of previous studies on compressible electrodes focus on carbon-based materials, whereas metal-based materials such as spinel metal oxide with faradaic nature have been rarely studied due to their lack of compressibility. Herein, NiCo2O4 (NCO) microtubes assembled by ultrathin and mesoporous nanosheets, are deposited on/into Ti3C2Tx MXene/reduced graphene oxide aerogel (MGA), an intrinsically compressible host template with high conductivity and specific surface areas. The optimized NCO/MGA-300 sample shows a reversible compressive strain of 60% and a superior durability. Density functional theory (DFT) calculations reveal that the NCO/MGA-300 heterojunction has high electronic conductivity, fast electron transfer ability, and low adsorption energy for OH- ions. As a result, the NCO/MGA-300 electrode exhibits superb electrochemical performance in terms of its high gravimetric capacitance (1633F g-1 at 1 A g-1), rate performance (1492F g-1 at 10 A g-1), and remarkable cycling stability of 86.6% after 10,000 charge-discharging cycles. Moreover, an assembled asymmetric supercapacitor based on compressible NCO/MGA-300 shows stable electrochemical performances under different compressive strains (20%. 40% and 60%), or after 100 compression-release cycles. This research finding demonstrates the possibility of metal-based electrode for wearable devices with high energy storage capability and good compressibility.
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Reasonable design of materials with complex nanostructures and diverse chemical compositions is of great significance in the field of energy storage. Cu7KS4 (CKS) is considered a potential electrode material for supercapacitors due to its superior electrical conductivity. Transition metal hydroxides are widely used as electrode materials for supercapacitors due to their high theoretical specific capacitance (Cs); however, single metal species with limited active sites restrict their further applications for energy storage. Herein, through a hydrothermal reaction, CKS nanorods were prepared, and then binary metal hydroxide NixCo1-x(OH)2 nanosheets were generated directly on CKS nanorods through a one-step hydrothermal reaction to form a nano-core-shell structure (NCSS). By regulating the mole ratio of nickel nitrate to cobalt nitrate, the resulting Ni0.75Co0.25(OH)2 nanosheets with the best electrochemical activity were prepared and supported on CKS nanorods to form a CKS@N0.75C0.25OH NCSS. The as-prepared CKS@N0.75C0.25OH NCSS has a larger specific surface area, which can provide more active sites, while the abundant metal species composition can generate abundant redox reactions to boost the pseudocapacitance. The prepared CKS@N0.75C0.25OH/NF electrode exhibits outstanding specific capacitance and cycle life. The assembled CKS@N0.75C0.25OH/NF//AC all-solid-state asymmetric supercapacitor achieves a high energy density of 88.7 Wh kg-1 at a power density of 849.9 W kg-1 with superior cycle life. Therefore, the use of polymetallic hydroxides to construct NCSS electrodes has great research significance and broad application prospects.
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INTRODUCTION: Colorectal liver metastasis is a challenge in the treatment of colorectal cancer and an important factor affecting the prognosis of patients. Currently, microwave ablation has gradually been applied for the treatment of liver cancers as a type of thermal ablation. However, there are no large-scale studies on the effectiveness of microwave ablation for colorectal liver metastases. AIM: To investigate the efficacy of microwave ablation and liver resection for liver metastases from colorectal cancer, and to compare the prognosis between patients treated with microwave ablation and those in the SEER (Surveillance, Epidemiology, and End Results, National Cancer Institute) database. MATERIAL AND METHODS: We retrospectively analyzed the clinical data of 24 patients with colorectal liver metastasis who underwent radical colorectal cancer resection and liver microwave ablation (the MWA group) and 12 patients who received radical colorectal cancer resection and liver resection (the LR group). The complete ablation rate and complications after microwave ablation were observed. Survival analysis was performed for cases treated with liver resection and cases from the SEER database. RESULTS: A total of 53 tumors were ablated in the 24 patients who underwent radical colorectal cancer resection and liver microwave ablation; 52 tumors achieved complete ablation after the first ablation (98.1%). No serious complications occurred in the MWA group, and long-term survival was not significantly different between the MWA and other groups. CONCLUSIONS: Microwave ablation for colorectal liver metastases avoids extensive liver resection while ensuring therapeutic efficacy; the operation is safe, feasible, and reproducible.
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The PEA3 subfamily is a subgroup of the E26 transformation-specific (ETS) family. Its members, ETV1, ETV4, and ETV5, have been found to be overexpressed in multiple cancers. The deregulation of ETV1, ETV4, and ETV5 induces cell growth, invasion, and migration in various tumor cells, leading to tumor progression, metastasis, and drug resistance. Therefore, exploring drugs or therapeutic targets that target the PEA3 subfamily may contribute to the clinical treatment of tumor patients. In this review, we introduce the structures and functions of the PEA3 subfamily members, systematically review their main roles in various tumor cells, analyze their prognostic and diagnostic value, and, finally, introduce several molecular targets and therapeutic drugs targeting ETV1, ETV4, and ETV5. We conclude that targeting a series of upstream regulators and downstream target genes of the PEA3 subfamily may be an effective strategy for the treatment of ETV1/ETV4/ETV5-overexpressing tumors.
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Background: The role of glutathione s-transferase genes (GSTP1, GSTM1 and GSTT1) variants and the GSTP1 expression level on chemotherapy efficacy of gastrointestinal cancer (GIC) patients were inconsistent. Methods: A meta-analysis about GSTP1, GSTM1 and GSTT1 variants and the GSTP1 expression level on chemotherapy efficacy of GIC patients was performed using data from PubMed, PMC, EMBASE, Web of Science, and Wanfang database. Results: Our meta-analysis enrolled 50 publications including 6518 patients. We found that patients with GIC harboring GSTP1 (IIe105Val) Val locus had higher objective response rates (ORR) than the IIe/IIe genotypic patients (odds ratio (OR) = 1.580, 95% confidence interval (CI) = 1.159-2.154, P = 0.004). Significant associations were found between the Ile105Val variant and overall survival of Caucasian GIC patients (IIe/Val vs. IIe/IIe: OR = 0.797 (0.674-0.944), P = 0.009). Caucasian GIC patients and gastric cancer patients with GSTT1 null genotype had worse response rates compared to GSTT1 present patients (OR = 0.530 (0.356-0.789), P = 0.002; OR = 0.643 (0.463-0.895), P = 0.009, respectively). Conclusion: This meta-analysis illustrates that GSTP1 IIe105Val and GSTT1 null/present variants could be useful predictors of chemotherapy efficacy in patients with gastrointestinal cancer.
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Colorectal cancer (CRC) is a common gastrointestinal cancer, with a high incidence and high mortality. Long non-coding RNAs (lncRNAs) are involved in the development, invasion and metastasis, early diagnosis, prognosis, the chemoresistance and radioresistance of CRC through interference with mRNA activity, directly combining with proteins to regulate their activity or alter their localization, influencing downstream gene expression by inhibiting RNA polymerase and regulating gene expression as competing endogenous RNAs. Recent progress in next generation sequencing and transcriptome analysis has revealed that tissue and cancer-type specific lncRNAs could be useful prognostic markers. Here, the CRC-associated lncRNAs from recent studies until October 2016 are reviewed and multiple studies that have confirmed CRC-associated lncRNAs are summarized. This review may be helpful in understanding the overall relationships between the lncRNAs involved in CRC.