Radiomics model based on multi-sequence MR images for predicting preoperative immunoscore in rectal cancer.

PURPOSE: To establish and validate a radiomics model based on multi-sequence magnetic resonance (MR) images for preoperative prediction of immunoscore in rectal cancer. MATERIALS AND METHODS: This retrospective study included 133 patients with pathologically confirmed rectal cancer after surgical resection who underwent MR examination before treatment within two weeks. All patients were randomly divided into training cohort (n = 92) and validation (n = 41) cohort according to a ratio of 7:3. The volumes of interest were manually delineated in the T2-weighted images (T2WI) and apparent diffusion coefficient (ADC) images, from which a total of 804 radiomics features were extracted. Thereafter, we used Spearman correlation analysis and gradient boosting decision tree (GBDT) algorithm to select the strongest features, and the radiomics scores were established using multivariate logistic regression algorithm, including two single-mode models and two dual-mode models. The predictive performance and the clinical usefulness of the model were assessed by the receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA). RESULTS: Integrated model A based on T2WI and ADC images showed a better predictive performance, which yielded an AUC of 0.770 (95% CI 0.673-0.867) in the training cohort and 0.768 (95% CI 0.619-0.917) in the validation cohort. Calibration curve showed good agreement between predicted results of the model and actual events, and DCA indicated good clinical usefulness. Moreover, stratification analysis proved that the integrated model A had strong robustness. CONCLUSIONS: Integrated model A based on T2WI and ADC images has the potential to be used as a non-invasive tool for preoperative prediction of immunoscore in rectal cancer. It may be useful in evaluating prognosis and guiding individualized immunotherapy of patients.

Engineering Solvation Complex-Membrane Interaction to Suppress Cation Crossover in 3 V Cu-Al Battery.

Metal-metal batteries such as the 3 V Cu-Al system are highly desirable for large-scale energy storage owing to their low cost and excellent scalability of Cu and Al foils. However, the dissolved Cu cations will crossover from the cathode to the anode leading to poor electrochemical performance. In this work, it is demonstrated that the reversibility of the Cu-Al battery depends strongly on the interaction of the Cu ions with the electrolyte solvent and subsequently the affinity of the solvated Cu ion with the membrane separator. Specifically, a series of common carbonate-based electrolyte solvents are investigated via molecular dynamics and contact angle measurements to understand the interaction between the solvents and a polypropylene (PP) membrane, as well as that between cations and solvent. Among different solvents, fluoroethylene carbonate (FEC) is shown to drastically enhance the coulombic efficiency to 97%, compared to that of 27% with dimethyl carbonate. Remarkable cyclability of a 3 V Cu-Al battery with 3 m LiTFSI FEC and PP membrane up to 1000 cycles is further demonstrated. This finding opens new opportunities for the development of low-cost, high performance Cu-Al systems for stationary applications.

Cobalt sulfide aerogel prepared by anion exchange method with enhanced pseudocapacitive and water oxidation performances.

This work introduces the anion exchange method into the sol-gel process for the first time to prepare a metal sulfide aerogel. A porous Co9S8 aerogel with a high surface area (274.2 m2 g-1) and large pore volume (0.87 cm3 g-1) has been successfully prepared by exchanging cobalt citrate wet gel in thioacetamide and subsequently drying in supercritical ethanol. Such a Co9S8 aerogel shows enhanced supercapacitive performance and catalytic activity toward oxygen evolution reaction (OER) compared to its oxide aerogel counterpart. High specific capacitance (950 F g-1 at 1 A g-1), good rate capability (74.3% capacitance retention from 1 to 20 A g-1) and low onset overpotential for OER (220 mV) were observed. The results demonstrated here have implications in preparing various sulfide chalcogels.

Thermal Stability of Graphite Electrode as Cathode for Dual-Ion Batteries.

The increasing number of accidents relating to battery fire and explosion is raising people's attention towards safety of batteries. Abnormal battery operation can generate much heat and cause thermal runaway due to the exothermic reactions of the electrodes and electrolyte. Recently, dual-ion battery (DIB) has gained many interests because of its low cost and high working voltage compared with traditional lithium-ion battery (LIB). However, investigation on thermal stability of DIB is rare. In this paper, differential scanning calorimetry (DSC) was used to study the thermal stability of DIB using graphite as cathode with different states of charge (SOC) and with different amount of fluoroethylene carbonate as co-solvent in the electrolyte. Then, the thermal stability of graphite cathode for DIB was compared with those of LiCoO2 and LiNi0.5 Mn1.5 O4 at their fully charged states. Specifically, charged DIB using graphite as cathode in 3 m LiPF6 EMC showed superior thermal stability with no exothermic peaks in DSC tests, in contrast to traditional lithium-containing cathodes for LIB, which gave out significant amount of heat at evaluated temperature. In addition, the thermal stability of graphite depended on the type of intercalation species in it. While PF6 - intercalated graphite [Cn (PF6 )] showed an endothermic peak at about 320 °C, Li+ intercalated graphite [Cn (Li)] showed an exothermic peak at about 300 °C. Moreover, the type of electrolyte also affected heat generation from the charged electrodes and should be properly designed to improve thermal stability in the future.

Chelating Polymer-Coated Separators with a BaTiO3 Filler To Improve Reversibility and Round-Trip Efficiency of a 3.3 V Copper-Lithium Battery.

A novel 3.3 V copper-lithium battery using a copper foil as the cathode is a potential candidate for next-generation energy storage system due to its simple manufacturing process. However, the cross-over of copper ions from the cathode to the anode limits the reversibility of the battery. Herein, we suppress self-discharge and migration of copper ions in the cell using a commercial polypropylene separator with a coating of polyacrylic acid (PAA), a chelating polymer. Fourier transform infrared spectroscopy confirms that the PAA layer traps the copper ions and prevents them from passing through. The addition of barium titanate nanoparticles into the PAA layer further enhances ionic transfer through the separator and reduces polarization of the cell at high current rates during charge and discharge. The use of a chelating agent with an inorganic filler as a coating layer on the separator is a cost-effective way to improve reversibility and round-trip efficiency of copper-lithium batteries.