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To explore the reaction mechanism of sludge, slag, lime, and fly ash in high temperature environments, the unconfined compressive strength (UCS) test was hereby implemented to study the effect on curing age, curing temperature, slag content and fly ash content about the strength of sludge. Scanning electron microscopy (SEM) was used to observe the microscopic composition of the substance, and X-ray diffraction (XRD) was used to analyze the mineral composition at the micro level to further disclose its reinforcement mechanism. The experimental results demonstrate the difference in the strength measured by different dosage of curing agent, and results indicate that the strength of high temperature curing sample was obviously higher than that of low temperature curing sample. When the curing temperature rises, the pozzolanic reaction and hydration reaction between materials are accelerated, and a certain amount of gel products are produced, playing a precipitation and bonding role between particles. The 28 days and 90 days strengths of the sludge samples with 20% fly ash and 80% slag dosing at 40°C were 1139 KPa and 1194 KPa, which were 1.4 and 1.1 times of that of pure cement solidified sludge. At 60°C, the strength of 14 days, 28 days and 90 days were 802 KPa, 1298 KPa and 1363 KPa, which were 1.1, 1.5 and 1.3 times of that of pure cement solidified sludge. Under the influence of an alkaline environment, the silicon-aluminum grid structure was interconnected into a denser network structure, and the compressive strength of lime-activated fly ash-slag was thus continuously enhanced. Affected by the high temperature, lime-activated fly ash-slag solidified sludge could significantly improve the middle and late strength of the sample. The research showed that the new solidification material can replace partly the concrete curing agent, thereby alleviating the carbon emission and environmental pollution problems arising from cement solidified sludge. [ABSTRACT FROM AUTHOR]

Background and Purpose: Predicting tumour response would be useful for selecting patients with locally advanced rectal cancer (LARC) for organ preservation strategies. We aimed to develop and validate a prediction model for T downstaging (ypT0-2) in LARC patients after neoadjuvant chemoradiotherapy and to identify those who may benefit from consolidation chemotherapy., Materials and Methods: cT3-4 LARC patients at three tertiary medical centers from January 2012 to January 2019 were retrospectively included, while a prospective cohort was recruited from June 2021 to March 2022. Eight filter (principal component analysis, least absolute shrinkage and selection operator, partial least-squares discriminant analysis, random forest)-classifier (support vector machine, logistic regression) models were established to select radiomic features. A nomogram combining radiomics and significant clinical features was developed and validated by calibration curve and decision curve analysis. Interaction test was conducted to investigate the consolidation chemotherapy benefits., Results: A total of 634 patients were included (426 in training cohort, 174 in testing cohort and 34 in prospective cohort). A radiomic prediction model using partial least-squares discriminant analysis and a support vector machine showed the best performance (AUC: 0.832 [training]; 0.763 [testing]). A nomogram combining radiomics and clinical features showed significantly better prognostic performance (AUC: 0.842 [training]; 0.809 [testing]) than the radiomic model. The model was also tested in the prospective cohort with AUC 0.727. High-probability group (score > 81.82) may have potential benefits from ≥ 4 cycles consolidation chemotherapy (OR: 4.173, 95 % CI: 0.953-18.276, p = 0.058, p interaction  = 0.021)., Conclusion: We identified and validated a model based on multicenter pre-treatment radiomics to predict ypT0-2 in cT3-4 LARC patients, which may facilitate individualised treatment decision-making for organ-preservation strategies and consolidation chemotherapy., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)