24 research outputs found

    Initial ablation ratio predicts the recurrence of low-risk papillary thyroid microcarcinomas treated with microwave ablation: a 5-year, single-institution cohort study

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    Objective: To assess the long-term efficacy and safety of microwave ablation (MWA) in treating low-risk papillary thyroid microcarcinomas (PTMC) and to identify predictive factors for the postoperative local tumor progression of PTMC. Methods: A total of 154 low-risk PTMC patients treated with MWA who were followed up for at least 3 months were retrospectively recruited. Ultrasonography was performed after MWA to assess the local tumor progression. Adverse events associated with MWA were recorded. The ablated volume (Va) and initial ablation ratio (IAR) were measured to assess their influences on the recurrence risk of PTMC. Results: The mean tumor volume of PTMC before MWA was 0.071 (0.039, 0.121) cm3, with a maximum diameter of 0.60 ± 0.18 cm. All PTMC patients were followed up for 6 (3, 18) months. Va increased immediately after MWA, then gradually decreased over time, till significantly smaller at 12 months than that before MWA (P 2.0 mU/L) of PTMC patients were not correlated with local tumor progression. Conclusion: MWA is an effective therapeutic strategy for low-risk PTMC with high safety. The maximum tumor diameter and IAR are predictive factors for the local tumor progression of PTMC after MWA

    Ultrasound-guided thermal ablation for papillary thyroid microcarcinoma: the devil is in the details

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    AbstractThermal ablation (TA) has harvested favorable outcomes in treating low-risk papillary thyroid microcarcinoma (PTMC). Preoperative assessment, intraoperative procedures and postoperative follow-up are all closely linked with the success and safety of TA on PTMC. However, many details in these aspects have not been systematically reviewed. This review firstly described the influence of preoperative assessment, especially for the risk of lymph node metastasis (LNM), as well as the molecular testing on the selection of TA for PTMC. Besides, we also summarized the experiences in treating special PTMC cases by TA, like multifocal lesions, PTMC located in the isthmus or adjacent to the dorsal capsule. At last, we discussed the follow-up strategies, the influence of the thyroid-stimulating hormone (TSH) level on the prognosis of PTMCs, and the management for recurrent cases. In conclusion, the procedures during the entire perioperative period should be standardized to improve the outcomes of TA in treating PTMC patients

    Ionic liquids: Functionalization and absorption of SO2

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    Room-temperature ionic liquids (ILs), which have excellent properties, such as high gas absorption abilities, extremely low volatility and tunable structures, are regarded as environmentally-friendly absorbents and widely used in SO2 absorption and separation. As a result, a large number of ILs have been synthesized to capture SO2 from flue gas or simulated gas, but a part of them just have physical interaction with SO2 and can hardly absorb SO2 when the content of SO2 is very low. Hence, functional ILs, which can chemically absorb a large amount of SO2 with low contents, have been designed and synthesized for SO2 capture. Up to now, many kinds of functional ILs were investigated for SO2 absorption from flue gas. In this review, the functional ILs are classified into guanidinium based ILs, hydroxyl ammonium based ILs, imidazolium/pyridinium based ILs, quaternary ammonium based ILs, phosphonium based ILs, and other kinds of ILs according to their cations. The capacities of SO2 absorption in these ILs, the mechanism of the absorption, and the ways to enhance the absorption are briefly introduced. The prospect of functional ILs for their application in SO2 removal is presented. The present problems and the further studies are also discussed. Keywords: Ionic liquid, SO2, Absorption, Functionalizatio

    Capture of Acidic Gases from Flue Gas by Deep Eutectic Solvents

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    Up to now, many kinds of deep eutectic solvents (DESs) were investigated for the capture of acidic gases from flue gases. In this review, non-functionalized and functionalized DESs, including binary and ternary DESs, for SO2, CO2 and NO capture, are summarized based on the mechanism of absorption, physical interaction or chemical reaction. New strategies for improving the absorption capacity are introduced in this review. For example, a third component can be introduced to form a ternary DES to suppress the increase in viscosity and improve the CO2 absorption capacity. DESs, synthesized with halogen salt hydrogen bond acceptors (HBAs) and functionalized hydrogen bond donors (HBDs), can be used for the absorption of SO2 and NO with high absorption capacities and low viscosities after absorption, due to physicochemical interaction between gases and DESs. Emphasis is given to introducing the absorption capacities of acidic gases in these DESs, the mechanism of the absorption, and the ways to enhance the absorption capacity

    A Decision-Making Model Using Machine Learning for Improving Dispatching Efficiency in Chengdu Shuangliu Airport

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    Due to the increasing number of people traveling by air, the passenger flow at the airport is increasing, and the problem of passenger drop-off and pickup has a huge impact on urban traffic. The difficulty of taking a taxi at the airport is still a hot issue in the society. Aiming at the problem of optimizing the allocation of taxi resource, this paper is based on the cost-benefit analysis method to determine the factors that affect the taxi driver’s decision-making. The mathematical methods such as function equation, BP neural network algorithm, and queuing theory were used to establish a complete decision-making model for taxi drivers and an optimization model of dispatching efficiency at the airport. A conclusion has been drawn that the allocation of airport taxi resource should be arranged closely related to drivers’ revenue and the layout of airport line

    Rapid Absorption and Desorption of CO<sub>2</sub> by Deep Eutectic Solvents via Reversible CO<sub>2</sub>‑Triggered Proton Transfer Process

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    Due to low cost and high efficiency, amino-based functionalized deep eutectic solvents (DESs) have been widely investigated in CO2 capture. The amino group reacted with CO2 in a quantized ratio of 2:1 to form a carbamate and quaternary ammonium cation, which not only limited the absorption capacity of the amino group but also led to a dramatic increase in viscosity. In this work, we proposed a new strategy to improve the absorption capacity of amino-based functionalized DESs and inhibit viscosity increase by changing the proton transfer site from –NH2 to –N to prevent the formation of –NH–COO– and –NH3+ using aromatic amines and ethylene glycol (EG). EG exhibited significant activation effect on 4-aminopyridine (AP). The absorption capacity of AP was enhanced from 0.10 mol of CO2/mol of DES to 0.60 mol of CO2/mol of DES at 303.15 K and 101.3 kPa after forming DES with EG. In addition, the saturated DES could be rapidly regenerated within 20 min at 353.15 K, and the absorption performance was maintained after six cycles. Results of proton nuclear magnetic resonance and carbon nuclear magnetic resonance spectra revealed the formation of carbamate and the protonation of pyridine nitrogen. The new reaction path effectively reduced the increase in viscosity. The viscosity of AP/EG (1:3) DES increased slightly from 29.17 to 68.40 mPa·s after absorption
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