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The establishment of reliable age in the lake sediment profile mainly depends on the AMS 14C dating technique. However, the presence of the 14C lake reservoir effects (LREs) restricted for using radiocarbon dating in lake sediment, especially in dry and cold areas with a scarce plant cover in the Qinghai-Tibet Plateau. Hence, the discussion of influence factors of LREs is crucial. This paper selected 15 lakes (17 sediment and 3 plant samples) in the Qinghai-Tibet Plateau to examine the distribution characteristics of the modern LREs and their main influencing factors. In our study area, 14 lakes were all affected by the LREs. The minimum 14C year is 5900 a BP towards the deep water area, whereas the maximum 14C year is up to 7185 a BP in the margins of Lake Heihai. The maximum 14C year is up to 7750 a BP, and the minimum 14C year is present-day carbon in the 15 lakes. One further study indicated that the LRE differences in individual lake are mostly owing to the contribution of exogenous carbonate. The results displayed that the LREs tended to increase with the increase of the salinity, moreover, the LREs of saltwater lakes or salt lakes were significantly larger than freshwater lakes due to the possible supply of old total dissolved inorganic carbon with a long residence time in the lakes. Moreover, the contribution of calcite played a significant role on the LREs. Additionally, the LREs differences are affected by the source of organic matter. The lake with groundwater supply shows large LRE due to likely being influenced by crustal and ancient CO2 uprising.

Proton conductivity of proton exchange membranes (PEMs) strongly relies on microscopic morphology, which can be modulated by engineering the distribution of ionic groups. Herein, poly(arylene ether)s with densely distributed allyl functionalities are polymerized from a tetra-allyl bisphenol A monomer. The subsequent thiol-ene addition with sodium 3-mercapto-1-propanesulfonate yields comb-shaped sulfonated fluorinated poly(arylene ether)s (SFPAEs) with ion exchange capacities (IECs) ranging from 1.29 mmol·g−1 to 1.78 mmol·g−1. These SFPAEs exhibit superior proton conductivity over the whole temperature range, which is attributed to the enhanced hydrophilic/hydrophobic phase separation as evidenced by small angle X-ray scattering characterizations. The SFPAE-4-40 with an IEC of 1.78 mmol·g−1 shows the largest proton conductivity of 93 mS·cm−1 at room temperature under fully hydrated condition, higher than that of Nafion 212. Furthermore, the vanadium redox flow battery (VRFB) assembled with SFPAE-4-40 separator exhibits higher energy efficiency than the VRFB assembled with Nafion 212.

This study aimed to explore the association of tumor sidedness with the prognosis of patients with colon signet ring cell carcinoma (SRCC). Eligible patients were retrieved from the Surveillance, Epidemiology, and End Results database between 2004 and 2015. Cancer-specific survival (CSS) and overall survival (OS) were compared between patients with left-sided colon SRCC and those with right-sided lesions. A total of 2660 patients were included, among them, 1983 (74.5%) had right-sided colon SRCC. Compared to patients with left-sided colon SRCC, those who had the right-sided colon SRCC showed higher proportion of white race, female, aged ≥ 65 years, receiving total colectomy and ≥ 4 regional lymph node dissection; while had lower proportion of advanced AJCC stage. Besides, right-sided patients exhibited superior 5-year CSS (32.74% vs. 25.89%, P = 0.001) and OS (27.38% vs. 23.02%, P = 0.024) rates compared with left-sided ones. Multivariate analysis revealed that tumor sidedness was an independent prognostic factor. To be specific, patients with right-sided colon SRCC showed better CSS (HR: 0.873; 95% CI 0.777–0.981; P = 0.023) and OS (HR: 0.838; 95% CI 0.753–0.965; P = 0.002). Moreover, subgroup analysis demonstrated superior CSS and OS for right-sided patients in most subgroups. Tumor sidedness was an independent prognostic indicator for colon SRCC. Besides, patients with right-sided colon SRCC have superior prognosis than those with left-sided lesions.

Bimetallic nanomaterials, which exhibit a combination of the properties associated with two different metals, have enabled innovative applications in nanoscience and nanotechnology. Here, we introduce the fabrication of dendritic Au/Ag bimetallic nanostructures for surface-enhanced Raman scattering (SERS) and catalytic applications. The dendritic Au/Ag bimetallic nanostructures were prepared by combining the electrochemical deposition and replacement reaction. The formation of Au nanoparticle shell on the surface of Ag dendrites greatly improves the stability of dendritic nanostructures, followed by a significant SERS enhancement. In addition, these dendritic Au/Ag bimetallic nanostructures are extremely efficient in degrading 4-nitrophenol (4-NP) compared with the initial dendritic Ag nanostructures. These experimental results indicate the great potential of the dendritic Au/Ag bimetallic nanostructures for the development of excellent SERS substrate and highly efficient catalysts.

In the study, a tunable dual-band terahertz hybrid metamaterial absorber was designed and explored. The proposed hybrid metamaterial absorber was composed of an Au ring, an Au cross structure and vanadium dioxide (VO2) films incorporated at the four ends of the cross structure. Theoretical simulation results showed that the hybrid metamaterial exhibited dual-frequency resonances. The low-frequency resonance was ascribed to the ring, whereas the high-frequency resonance was ascribed to the cross structure. The resonant frequencies of the hybrid metamaterial absorber could be tuned by changing the effective length of electrically resonant cross structure through triggering the insulator–metal phase transition of the VO2 at the four ends of the cross structure.