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Abstract Purpose To compare the safety and efficacy of CPG in the rectus abdominis and intercostal regions. Materials and methods This retrospective study included 226 patients who underwent CPG at a single center, with the stoma placed in the rectus abdominis or intercostal region. Surgical outcomes and complications, such as pain and infection within 6 months postoperatively, were recorded. Results The surgical success rate was 100%, and the all-cause mortality rate within 1 month was 0%. An intercostal stoma was placed in 56 patients; a rectus abdominis stoma was placed in 170 patients. The duration of surgery was longer for intercostal stoma placement (37.66 ± 14.63 min) than for rectus abdominis stoma placement (30.26 ± 12.40 min) (P = 0.000). At 1 month postsurgery, the rate of stoma infection was greater in the intercostal group (32.1%) than in the rectus abdominis group (20.6%), but the difference was not significant (P = 0.077). No significant difference was observed in the infection rate between the two groups at 3 or 6 months postsurgery (P > 0.05). Intercostal stoma patients reported higher pain scores during the perioperative period and at 1 month postsurgery (P = 0.000), but pain scores were similar between the two groups at 3 and 6 months postsurgery. The perioperative complication rates for intercostal and rectus abdominis surgery were 1.8% and 5.3%, respectively (P = 0.464), with no significant difference in the incidence of tube dislodgement (P = 0.514). Patient weight improved significantly at 3 and 6 months postoperatively compared to preoperatively (P

Sampling of training data is the most important step in active learning slope reliability analysis, which controls the analysis accuracy. In this study, a novel surrogate-assisted normal search particle swarm optimization (SANSPSO) was proposed to enhance the accuracy and robustness of existing methodologies. In SANSPSO, the sampling process was considered a minimum problem with an objective function defined as the absolute value of the performance function. Initiated with a normal search paradigm and supplemented by three algorithm strategies, this approach seeks to preserve the continuity of the solution while refining the algorithm's efficacy and efficiency. To reduce computation cost, surrogate-assistance was used, in which a surrogate model substitutes the objective function in most iterations. This surrogate model evolves during the iteration process and ultimately replaces the actual performance function within Monte Carlo simulation. Finally, this study presents a comparative study with five state-of-the-art methods across four explicit problems and three engineering cases, where test data suggest that the SANSPSO methodology yields a 20% improvement in accuracy and a 30% rise in stability under different dimensional problems relative to the most efficacious of the alternate methods assessed because of the improved and more consistent prediction of limit state function. These findings substantiate the validity and robustness of the SANSPSO approach. [ABSTRACT FROM AUTHOR]

Over the years, it has become obvious that simultaneous backfill grouting is of great significance to the design of the tunnel lining and process control of shield construction. It is essential to know the grout pressure distribution around the tunnel lining. The purpose of this study is to seek an alternative method to simulate the grout diffusion process and obtain pressure distribution of different time during simultaneous backfill grouting of tunnel construction. A lattice Boltzmann method (LBM) based free surface flow model is introduced and modified, and a Smagorinsky large-eddy simulation model serves to deal with the small-scale turbulent problem, which is a challenge for LBM to simulate the large-scale real-world engineering. The simulation results obtain the grout filling state with time and pressure distribution around the tunnel lining. Additionally, the grout pressures on site are measured at a ring in line 8 of Chengdu Rail tunnel, and the measurement results are also compared with ones taken from numerical simulation, it is showed that the numerical results are consistent with that of measurement on the whole. Through simulating different grouting strategies, it is concluded that for four-holes grouting schemes, the grouting pressures of upper holes are significant for the grout pressure distribution and should be paid most attention in construction. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of ethyl alpha-(2-alkenyl)-alpha-(per(poly)fluoroacyl)acetates was developed based on tandem reactions involving ethyl alpha(per-(poly)fluoroalkyl)acetates. The synthetic process was characterized by the formation of the target compound from the reaction of allylic alcohols with ethyl alpha-(per(poly)fluoroalkyl)acetates in the presence of a mixed base. Furthermore, the resulting products can be utilized as starting materials for the synthesis of fluorine-containing heterocyclic compounds.