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Preoperative assessment of lymph node metastasis (LNM) status is the basis of individual treatment for rectal cancer (RC). However, conventional imaging methods are not accurate enough.

We collected 282 RC patients who were divided into the training dataset (n=225) and the test dataset (n=57) with an 8:2 scale. A large number of deep learning (DL) features and hand-crafted radiomics (HCR) features of primary tumors were extracted from the arterial and venous phases of the computed tomography (CT) images. Three machine learning models, including support vector machine (SVM), k-nearest neighbor (KNN),and multi-layer perceptron (MLP) were utilized to predict LNM status in RC patients. A stacking nomogram was constructed by selecting optimal machine learning models for arterial and venous phases, respectively, combined with predictive clinical features.

The stacking nomogram performed well in predicting LNM status, with an area under the curve (AUC) of 0.914 [95% confidence interval (CI): 0.874-0.953] in the training dataset, and an AUC of 0.942 (95%CI: 0.886-0.997) in the test dataset. The AUC of the stacking nomogram were higher than those of CT_reported_N_status, ASVM, and VSVM model in the training dataset (P <0.05). However, in the test dataset, although the AUC of the stacking nomogram was higher than the VSVM, the difference was not obvious (P =0.1424).

The developed deep learning radiomics stacking nomogram showed to be effective in predicting the preoperative LNM status in RC patients.

To perform a comparison of the plan quality between volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) for multiple liver metastases using single-isocenter stereotactic body radiotherapy (SBRT).

Twenty-one patients who developed two or three adjacent liver metastases were included. For every patient, both VMAT and IMRT plans were replanned respectively for SBRT treatment. Dosimetric parameters, including the mean dose for the planning target volume, conformity index (CI), homogeneity index (HI) and gradient index (GI), were evaluated. Normal tissue sparing was also investigated. Finally, the total delivered monitor units (MUs) for both groups of treatment plans during irradiation were measured and compared.

Both groups of treatment plans satisfied normal tissue tolerance and produced clinically accepted dose distributions. The VMAT plans provided higher values of HI and GI as well as similar CI values in comparison with the IMRT plans. In addition, the VMAT plans obtained ultimately a improved mean dose to the target and a reduced dose to the organs at risk. However, there were no statistically significant differences in the V7Gy and D700cc of healthy liver, the mean dose and V15Gy of the ipsilateral kidney, the mean dose to the stomach, and the maximum dose to the heart between the two groups. Finally, the VMAT plans showed fewer MUs than the IMRT plans.

The plan quality of single-isocenter VMAT plans is superior to that of IMRT plans for the SBRT treatment of multiple metastatic liver tumors from the perspective of pure physical parameters.

As one of the core components of the fire-fighting water-supply system, the performance of a fire pump directly determines the extent of damage caused by the fire. Compared with conventional pumps, the design requirements of fire pumps not only need to ensure that the head of the pump is at 0Qd, 1.0Qd, and 1.5Qd and its efficiency is at 1.0Qd but also consider the cavitation performance at each flow rate, which presents a greater challenge for the design of high-performance fire pumps. By optimizing the design of a centrifugal fire pump with a specific speed of 24.7, numerical calculations were performed to obtain the best optimized scheme Y4. The results show that at the design flow rate the best optimized scheme improves the efficiency by 9.17% compared with the original scheme, and the head meets the design requirements of the fire pump while avoiding the hump phenomenon. Through a comparative analysis, it was found that the optimized scheme Y4 can reduce the pressure pulsations at the outlet of the pump and improve the cavitation performance at each flow rate. The experiment verifies that the head of the best optimized scheme at the design flow rate is 74.43m, the pump efficiency is 40.22%, and there is no hump in the head curve, which can meet the design and use requirements of the fire pump. The maximum reduction in the outlet pressure pulsations coefficient in the best optimized scheme was 47.12% on average. Compared with the original scheme, the critical net positive suction head (NPSHr) of the best optimized scheme was reduced by 21.5%, 17.6%, 15.7%, and 16.8%, respectively.

A reliable agent addition control is crucial for the foam technology that is prevalent in many industrial fields. The objective of this paper is to reveal the precise quantitative control mechanism and distinctive performance of cavitation jet. The cavitation evolution suction process is analyzed by the vapor appearance order defined. A 5-6 mm vapor-liquid transition interface is found in the cavitation jet with a remarkable mutation in fluid pressure, density and velocity. The vapor region in the jet device decreases and the maximum vapor volume fraction declines from 96.4% to 0 as the pressure ratio increases. The precise quantitative control is realized by the cavitation jet at the negative pressure less than -87 kPa in the suction port. The absorption amount decreases with the absorbed liquid viscosity increasing and a various level of precise quantitative control is achieved by the orifice plate area. The relation between the absorption amount and plate area is quadratic curve. Furthermore, the dust suppression practical was successfully conducted in a coal bunker to verify the effectiveness of foam technology using cavitation jet. Based on the above contribution, it is believed that the proposed precise quantitative control method has a strong applicability and popularization in industrial control field.

Plasma electrolytic oxidation was employed for producing alumina, alumina/titania composite and alumina/ titania composite coatings containing sodium tungstate additive. These coatings were produced in a silicatebased electrolyte on 7075 aluminum alloy using unipolar and bipolar waveforms with anodic/cathodic duty aspect ratios of 1 and 0.5. The results showed that the morphology of the coatings surfaces depends on the used waveform. By increasing the cathodic duty cycle, pancake-like morphology was converted to crater-like one. The incorporation of TiO2 nano-particles into the coatings, led to the widening the micro-pores when unipolar waveforms were used. The results revealed that the incorporation of TiO2 nano-particles doesn’t depend on the used waveforms. Titania nano-particles were incorporated into the coatings via a physical entrapping mechanism, while the adsorption mechanism of tungstate ions was electrophoretic. The corrosion resistance of the coatings was increased by increasing the cathodic duty cycle. Furthermore, the use of titania nanoparticles led to a reduction of corrosion resistance and the use of tungstate additive in bipolar waveform compensated the reduced resistance. The corrosion currents recorded 3, 5 and 3 nano-amperes for simple, composite and additive contained composite coatings respectively.